Copying modules from Equinox branch, to start merging the delta changes from 1.x/original trunk

git-svn-id: http://svn.us.apache.org/repos/asf/tuscany@718815 13f79535-47bb-0310-9956-ffa450edef68

80 files changed, 6863 insertions, 0 deletions

diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Artifact.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Artifact.java
new file mode 100644
index 0000000000..7400501d85
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Artifact.java
@@ -0,0 +1,86 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+import org.apache.tuscany.sca.assembly.Base;
+
+
+/**
+ * Represents an artifact in an SCA contribution.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface Artifact extends Base {
+    
+    /**
+     * Returns the URI that unique identifies the artifact inside the contribution.
+     * 
+     * @return The artifact URI
+     */
+    String getURI();
+    
+    /**
+     * Sets the URI that uniquely identifies the artifact inside the contribution.
+     * 
+     * @param uri The artifact URI
+     */
+    void setURI(String uri);
+
+    /**
+     * Returns the location of the artifact.
+     * 
+     * @return The artifact location
+     */
+    String getLocation();
+    
+    /**
+     * Set the location of the artifact.
+     * 
+     * @param location The artifact location
+     */
+    void setLocation(String location);
+
+    
+    /**
+     * Returns the in-memory model representing the artifact.
+     * 
+     * @return The model object
+     */
+    Object getModel();
+    
+    /**
+     * Sets the in-memory model representing the artifact.
+     * 
+     * @param model The model object
+     */
+    void setModel(Object model);
+
+    /**
+     * Returns the contents of the artifact cached here.
+     * @return the contents of the artifact
+     */
+    byte[] getContents();
+    
+    /**
+     * Sets the contents of the artifact.
+     * @param contents the contents of the artifact
+     */
+    void setContents(byte[] contents);
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Constants.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Constants.java
new file mode 100644
index 0000000000..4cf20125b9
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Constants.java
@@ -0,0 +1,30 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+/**
+ * Constants used in SCA contribution.
+ *
+ * @version $Rev$ $Date$
+ */
+public interface Constants {
+    String SCA10_NS = "http://www.osoa.org/xmlns/sca/1.0";
+    String SCA10_TUSCANY_NS = "http://tuscany.apache.org/xmlns/sca/1.0";
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/ContentType.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/ContentType.java
new file mode 100644
index 0000000000..81b0b08b9d
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/ContentType.java
@@ -0,0 +1,40 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+/**
+ * Constants for the main supported contribution package type.
+ * 
+ * @version $Rev$ $Date$
+ */
+@Deprecated
+public interface ContentType {
+    
+    /**
+     * Java compressed contribution package
+     */
+    String JAR = "application/x-compressed";
+
+    /**
+     * Filesystem folder contribution package
+     */
+    String FOLDER = "application/vnd.tuscany.folder";
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Contribution.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Contribution.java
new file mode 100644
index 0000000000..80dece4496
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Contribution.java
@@ -0,0 +1,123 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+import java.util.List;
+
+import org.apache.tuscany.sca.assembly.Composite;
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+
+/**
+ * The representation of an SCA contribution.
+ *
+ * @version $Rev$ $Date$
+ */
+public interface Contribution extends Artifact {
+    
+    /**
+     * Default location of contribution metadata in an SCA contribution.
+     */
+    String SCA_CONTRIBUTION_META = "META-INF/sca-contribution.xml";
+    
+    /**
+     * Default location of a generated contribution metadata in an SCA contribution.
+     */
+    String SCA_CONTRIBUTION_GENERATED_META = "META-INF/sca-contribution-generated.xml";
+    
+    /**
+     * Default location of deployable composites in an SCA contribution.
+     */
+    String SCA_CONTRIBUTION_DEPLOYABLES = "META-INF/sca-deployables/";
+
+    
+    /**
+     * Returns a list of exports based on the contribution metadata.
+     * 
+     * @return The list of exports in this contribution
+     */
+    List<Export> getExports();
+
+    /**
+     * Returns a list of imports based on the contribution metadata.
+     * 
+     * @return The list of imports in this contribution
+     */
+    List<Import> getImports();
+    
+    /**
+     * Returns the list of deployable composites in the contribution.
+     * 
+     * @return The list of deployable composites
+     */
+    List<Composite> getDeployables();
+
+    /**
+     * Returns the list of artifacts in the contribution.
+     * 
+     * @return The list of artifacts in the contribution
+     */
+    List<Artifact> getArtifacts();
+
+    /**
+     * Returns the model resolver for the models representing the artifacts
+     * visible in the scope of this contribution.
+     * 
+     * @return The model resolver
+     */
+    ModelResolver getModelResolver();
+    
+    /**
+     * Sets the model resolver for the models representing the artifacts
+     * visible in the scope of this contribution.
+     * 
+     * @param modelResolver The model resolver
+     */
+    void setModelResolver(ModelResolver modelResolver);
+    
+    /**
+     * Returns the list of contributions that this contribution depends on.
+     * 
+     * @return
+     */
+    List<Contribution> getDependencies();
+    
+    /**
+     * Returns the ClassLoader used to load classes and resources from
+     * this contribution
+     * 
+     * FIXME Remove this, the base contribution model should not depend
+     * on Java ClassLoaders. 
+     * 
+     * @return The contribution ClassLoader
+     */
+    ClassLoader getClassLoader();
+    
+    /**
+     * Sets the ClassLoader used to load classes and resources from
+     * this contribution
+     * 
+     * FIXME Remove this, the base contribution model should not depend
+     * on Java ClassLoaders. 
+     * 
+     * @param classLoader the contribution class loader
+     */
+    void setClassLoader(ClassLoader classLoader);
+    
+}
\ No newline at end of file
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/ContributionFactory.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/ContributionFactory.java
new file mode 100644
index 0000000000..67c9a05a0b
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/ContributionFactory.java
@@ -0,0 +1,73 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+
+/**
+ * A factory for the contribution model.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface ContributionFactory {
+    
+    /**
+     * Create a contribution model object
+     * 
+     * @return The new contribution model object
+     */
+    Contribution createContribution();
+        
+    /**
+     * Create a contribution metadata model object
+     * 
+     * @return The new contribution metadata model object
+     */
+    ContributionMetadata createContributionMetadata();
+        
+    /**
+     * Create a deployedArtifact model object
+     * 
+     * @return The new deployedArtifact model object
+     */
+    @Deprecated
+    DeployedArtifact createDeployedArtifact();   
+
+    /**
+     * Create an artifact model object
+     * 
+     * @return The new artifact model object
+     */
+    Artifact createArtifact();
+
+    /**
+     * Create a default import model object.
+     * 
+     * @return the new default import model object
+     */
+    DefaultImport createDefaultImport();
+
+    /**
+     * Create a default export model object.
+     * 
+     * @return the new default export model object
+     */
+    DefaultExport createDefaultExport();
+    
+}
\ No newline at end of file
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/ContributionMetadata.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/ContributionMetadata.java
new file mode 100644
index 0000000000..4043fb9eda
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/ContributionMetadata.java
@@ -0,0 +1,55 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+import java.util.List;
+
+import org.apache.tuscany.sca.assembly.Base;
+import org.apache.tuscany.sca.assembly.Composite;
+
+/**
+ * The representation of SCA contribution metadata.
+ *
+ * @version $Rev$ $Date$
+ */
+public interface ContributionMetadata extends Base {
+    
+    /**
+     * Returns a list of exports based on the contribution metadata.
+     * 
+     * @return The list of exports
+     */
+    List<Export> getExports();
+
+    /**
+     * Returns a list of imports based on the contribution metadata.
+     * 
+     * @return The list of imports
+     */
+    List<Import> getImports();
+    
+    /**
+     * Returns the list of deployable based on the contribution metadata.
+     * 
+     * @return The list of deployable composites
+     */
+    List<Composite> getDeployables();
+
+}
\ No newline at end of file
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DefaultContributionFactory.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DefaultContributionFactory.java
new file mode 100644
index 0000000000..98954c288a
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DefaultContributionFactory.java
@@ -0,0 +1,32 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+import org.apache.tuscany.sca.contribution.impl.ContributionFactoryImpl;
+
+
+/**
+ * Default implementation of a contribution model factory.
+ * 
+ * @version $Rev$ $Date$
+ */
+public class DefaultContributionFactory extends ContributionFactoryImpl {
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DefaultExport.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DefaultExport.java
new file mode 100644
index 0000000000..b2eddb8336
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DefaultExport.java
@@ -0,0 +1,30 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+
+/**
+ * The representation of an export that exports all artifacts in
+ * a contribution.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface DefaultExport extends Export {
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DefaultImport.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DefaultImport.java
new file mode 100644
index 0000000000..20798dcd17
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DefaultImport.java
@@ -0,0 +1,30 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+
+/**
+ * The representation of a default import that imports artifacts from
+ * all contributions.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface DefaultImport extends Import {
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DeployedArtifact.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DeployedArtifact.java
new file mode 100644
index 0000000000..ffe190132c
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/DeployedArtifact.java
@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+/**
+ * Representation of a deployed artifact
+ *
+ * @version $Rev$ $Date$
+ */
+@Deprecated
+public interface DeployedArtifact extends Artifact {
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Export.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Export.java
new file mode 100644
index 0000000000..bfa16b1ce3
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Export.java
@@ -0,0 +1,47 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+
+/**
+ * The representation of an export.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface Export {
+
+    /**
+     * Returns the model resolver for the models representing artifacts
+     * made available by this export.
+     * 
+     * @return The model resolver
+     */
+    ModelResolver getModelResolver();
+    
+    /**
+     * Sets the model resolver for the models representing artifacts
+     * made available by this export.
+     * 
+     * @param modelResolver
+     */
+    void setModelResolver(ModelResolver modelResolver);
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Import.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Import.java
new file mode 100644
index 0000000000..35076f55a7
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/Import.java
@@ -0,0 +1,56 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+
+
+/**
+ * The representation of an import.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface Import {
+
+    /**
+     * Returns the model resolver for the models representing artifacts
+     * made available by this import.
+     * 
+     * @return The model resolver
+     */
+    ModelResolver getModelResolver();
+
+    /**
+     * Sets the model resolver for the models representing artifacts
+     * made available by this import.
+     * 
+     * @param modelResolver The model resolver
+     */
+    void setModelResolver(ModelResolver modelResolver);
+    
+    /**
+     * Verify that a specific export actually exports what is being imported.
+     * 
+     * @param export The Exported being verified
+     * @return true/false
+     */
+    boolean match(Export export);
+    
+}
\ No newline at end of file
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/PackageType.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/PackageType.java
new file mode 100644
index 0000000000..c0dd5431d7
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/PackageType.java
@@ -0,0 +1,42 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution;
+
+/**
+ * Constants for the main supported contribution package types.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface PackageType {
+    
+    /**
+     * Java compressed contribution package
+     */
+    String JAR = "application/x-compressed";
+
+    /**
+     * Filesystem folder contribution package
+     */
+    String FOLDER = "application/vnd.tuscany.folder";
+    
+    
+    String BUNDLE = "application/osgi.bundle";
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ArtifactImpl.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ArtifactImpl.java
new file mode 100644
index 0000000000..881987f622
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ArtifactImpl.java
@@ -0,0 +1,103 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.impl;
+
+import org.apache.tuscany.sca.contribution.Artifact;
+
+
+/**
+ * The model representing an artifact in a contribution.
+ * 
+ * @version $Rev$ $Date$
+ */
+class ArtifactImpl implements Artifact {
+    private String uri;
+    private String location;
+    private Object model;
+    private boolean unresolved;
+    private byte[] contents;
+
+    ArtifactImpl() {
+    }
+    
+    public String getLocation() {
+        return location;
+    }
+
+    public void setLocation(String location) {
+        this.location = location;
+    }
+    
+    public String getURI() {
+        return uri;
+    }
+    
+    public void setURI(String uri) {
+        this.uri = uri;
+    }
+    
+    public Object getModel() {
+        return model;
+    }
+    
+    public void setModel(Object model) {
+        this.model = model;
+    }
+
+    public byte[] getContents() {
+        return contents;
+    }
+    
+    public void setContents(byte[] contents) {
+        this.contents = contents;
+    }
+    
+    public boolean isUnresolved() {
+        return unresolved;
+    }
+    
+    public void setUnresolved(boolean unresolved) {
+        this.unresolved = unresolved;
+    }
+
+    @Override
+    public int hashCode() {
+        return uri.hashCode();
+    }
+    
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == this) {
+            return true;
+        } else {
+            if (obj instanceof Artifact) {
+                return uri.equals(((Artifact)obj).getURI());
+            } else {
+                return false;
+            }
+        }
+    }
+
+    @Override
+    public String toString() {
+    	return "Artifact:" + uri + "\n" +
+    	       "at: " + location;
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ContributionFactoryImpl.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ContributionFactoryImpl.java
new file mode 100644
index 0000000000..c678c2eaef
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ContributionFactoryImpl.java
@@ -0,0 +1,67 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.impl;
+
+import org.apache.tuscany.sca.contribution.Artifact;
+import org.apache.tuscany.sca.contribution.Contribution;
+import org.apache.tuscany.sca.contribution.ContributionFactory;
+import org.apache.tuscany.sca.contribution.ContributionMetadata;
+import org.apache.tuscany.sca.contribution.DefaultExport;
+import org.apache.tuscany.sca.contribution.DefaultImport;
+import org.apache.tuscany.sca.contribution.DeployedArtifact;
+
+
+/**
+ * Default implementation of a contribution model factory.
+ * 
+ * @version $Rev$ $Date$
+ */
+public class ContributionFactoryImpl implements ContributionFactory {
+    
+    protected ContributionFactoryImpl() {
+    }
+    
+    public Contribution createContribution() {
+        return new ContributionImpl();
+    }
+    
+    public ContributionMetadata createContributionMetadata() {
+        return new ContributionMetadataImpl();
+    }
+
+    public Artifact createArtifact() {
+        return new ArtifactImpl();
+    }
+    
+    public DefaultExport createDefaultExport() {
+        return new DefaultExportImpl();
+    }
+    
+    public DefaultImport createDefaultImport() {
+        return new DefaultImportImpl();
+    }
+    
+    @Deprecated
+    public DeployedArtifact createDeployedArtifact() {
+        class DeployedArtifactImpl extends ArtifactImpl implements DeployedArtifact {
+        }
+        return new DeployedArtifactImpl();
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ContributionImpl.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ContributionImpl.java
new file mode 100644
index 0000000000..0b41016caa
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ContributionImpl.java
@@ -0,0 +1,159 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.impl;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.tuscany.sca.assembly.Composite;
+import org.apache.tuscany.sca.contribution.Artifact;
+import org.apache.tuscany.sca.contribution.Contribution;
+import org.apache.tuscany.sca.contribution.Export;
+import org.apache.tuscany.sca.contribution.Import;
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+
+/**
+ * The representation of a deployed contribution
+ *
+ * @version $Rev$ $Date$
+ */
+class ContributionImpl implements Contribution {
+    private String uri;
+    private String location;
+    private Object model;
+    private byte[] contents;
+    private boolean unresolved;
+    private List<Export> exports = new ArrayList<Export>();
+    private List<Import> imports = new ArrayList<Import>();
+    private List<Composite> deployables = new ArrayList<Composite>();
+    private List<Artifact> artifacts = new ArrayList<Artifact>();
+    private List<Contribution> dependencies = new ArrayList<Contribution>();
+    private ModelResolver modelResolver;
+    
+    // FIXME remove this dependency on Java ClassLoaders
+    private ClassLoader classLoader;
+
+    ContributionImpl() {
+    }
+    
+    public String getLocation() {
+        return this.location;
+    }
+
+    public void setLocation(String location) {
+        this.location = location;
+    }
+
+    //FIXME Remove dependency on Java ClassLoaders
+    public ClassLoader getClassLoader() {
+        return classLoader;
+    }
+    
+    //FIXME Remove dependency on Java ClassLoaders
+    public void setClassLoader(ClassLoader classLoader) {
+        this.classLoader = classLoader;
+    }
+    
+    
+    public String getURI() {
+        return this.uri;
+    }
+    
+    public void setURI(String uri) {
+        this.uri = uri;
+    }
+
+    public Object getModel() {
+        return model;
+    }
+    
+    public void setModel(Object model) {
+        this.model = model;
+    }
+    
+    public byte[] getContents() {
+        return contents;
+    }
+    
+    public void setContents(byte[] contents) {
+        this.contents = contents;
+    }
+    
+    public boolean isUnresolved() {
+        return unresolved;
+    }
+    
+    public void setUnresolved(boolean unresolved) {
+        this.unresolved = unresolved;
+    }
+    
+    public ModelResolver getModelResolver() {
+        return modelResolver;
+    }
+
+    public void setModelResolver(ModelResolver modelResolver) {
+        this.modelResolver = modelResolver;
+    }
+    
+    public List<Contribution> getDependencies() {
+        return dependencies;
+    }
+    
+    public List<Export> getExports() {
+        return exports;
+    }
+
+    public List<Import> getImports() {
+        return imports;
+    }
+
+    public List<Composite> getDeployables() {
+        return deployables;
+    }
+
+    public List<Artifact> getArtifacts() {
+        return artifacts;
+    }
+
+    @Override
+    public int hashCode() {
+        return uri.hashCode();
+    }
+    
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == this) {
+            return true;
+        } else {
+            if (obj instanceof Artifact) {
+                return uri.equals(((Artifact)obj).getURI());
+            } else {
+                return false;
+            }
+        }
+    }
+
+    @Override
+    public String toString() {
+    	return "Contribution : " + uri + " \n" +
+    	       "from: " + location;
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ContributionMetadataImpl.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ContributionMetadataImpl.java
new file mode 100644
index 0000000000..75b12b1260
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/ContributionMetadataImpl.java
@@ -0,0 +1,64 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.impl;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.tuscany.sca.assembly.Composite;
+import org.apache.tuscany.sca.contribution.ContributionMetadata;
+import org.apache.tuscany.sca.contribution.Export;
+import org.apache.tuscany.sca.contribution.Import;
+
+/**
+ * The representation of a deployed contribution
+ *
+ * @version $Rev$ $Date$
+ */
+class ContributionMetadataImpl implements ContributionMetadata {
+    private boolean unresolved;
+    private List<Export> exports = new ArrayList<Export>();
+    private List<Import> imports = new ArrayList<Import>();
+    private List<Composite> deployables = new ArrayList<Composite>();
+
+    ContributionMetadataImpl() {
+    }
+    
+    public boolean isUnresolved() {
+        return unresolved;
+    }
+    
+    public void setUnresolved(boolean unresolved) {
+        this.unresolved = unresolved;
+    }
+    
+    public List<Export> getExports() {
+        return exports;
+    }
+
+    public List<Import> getImports() {
+        return imports;
+    }
+
+    public List<Composite> getDeployables() {
+        return deployables;
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/DefaultExportImpl.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/DefaultExportImpl.java
new file mode 100644
index 0000000000..e67395337a
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/DefaultExportImpl.java
@@ -0,0 +1,45 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.impl;
+
+import org.apache.tuscany.sca.contribution.DefaultExport;
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+
+/**
+ * The representation of an export for the contribution
+ * 
+ * @version $Rev$ $Date$
+ */
+public class DefaultExportImpl implements DefaultExport {
+    private ModelResolver modelResolver;
+    
+    protected DefaultExportImpl() {
+        super();
+    }
+    
+    public ModelResolver getModelResolver() {
+        return modelResolver;
+    }
+    
+    public void setModelResolver(ModelResolver modelResolver) {
+        this.modelResolver = modelResolver;
+    }
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/DefaultImportImpl.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/DefaultImportImpl.java
new file mode 100644
index 0000000000..17c09f2cbc
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/impl/DefaultImportImpl.java
@@ -0,0 +1,55 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.impl;
+
+import org.apache.tuscany.sca.contribution.DefaultExport;
+import org.apache.tuscany.sca.contribution.DefaultImport;
+import org.apache.tuscany.sca.contribution.Export;
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+
+/**
+ * The representation of an import for the contribution
+ * 
+ * @version $Rev$ $Date$
+ */
+public class DefaultImportImpl implements DefaultImport {
+    private ModelResolver modelResolver;
+
+    protected DefaultImportImpl() {
+        super();
+    }
+    
+    public ModelResolver getModelResolver() {
+        return modelResolver;
+    }
+    
+    public void setModelResolver(ModelResolver modelResolver) {
+        this.modelResolver = modelResolver;
+    }
+
+    
+    public boolean match(Export export) {
+        if (export instanceof DefaultExport) {
+            return true;
+        }
+        return false;
+    }
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ArtifactProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ArtifactProcessor.java
new file mode 100644
index 0000000000..5be0b188f4
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ArtifactProcessor.java
@@ -0,0 +1,47 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+
+/**
+ * Base interface for artifact processors.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface ArtifactProcessor<M> {
+    
+    /**
+     * Resolve references from this model to other models. For example references
+     * from a composite to another one, or references from a composite to a WSDL
+     * model.
+     * 
+     * @param model The model to resolve
+     * @param resolver The resolver to use to resolve referenced models
+     */
+    void resolve(M model, ModelResolver resolver) throws ContributionResolveException;
+    
+    /**
+     * Returns the type of model handled by this artifact processor.
+     * 
+     * @return The type of model handled by this artifact processor
+     */
+    Class<M> getModelType(); 
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ArtifactProcessorExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ArtifactProcessorExtensionPoint.java
new file mode 100644
index 0000000000..029df61f0f
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ArtifactProcessorExtensionPoint.java
@@ -0,0 +1,58 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+/**
+ * An extension point for artifact processors.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface ArtifactProcessorExtensionPoint<P extends ArtifactProcessor> {
+
+    /**
+     * Add an artifact processor.
+     * 
+     * @param artifactProcessor The artifact processor to add
+     */
+    void addArtifactProcessor(P artifactProcessor);
+
+    /**
+     * Remove an artifact processor.
+     * 
+     * @param artifactProcessor The artifact processor to remove
+     */
+    void removeArtifactProcessor(P artifactProcessor);
+
+    /**
+     * Returns the processor associated with the given artifact type.
+     * 
+     * @param artifactType An artifact type
+     * @return The processor associated with the given artifact type
+     */
+    P getProcessor(Object artifactType);
+    
+    /**
+     * Returns the processor associated with the given model type.
+     * 
+     * @param modelType A model type
+     * @return The processor associated with the given model type
+     */
+    P getProcessor(Class<?> modelType);
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/BaseStAXArtifactProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/BaseStAXArtifactProcessor.java
new file mode 100644
index 0000000000..f23797a831
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/BaseStAXArtifactProcessor.java
@@ -0,0 +1,539 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import static javax.xml.stream.XMLStreamConstants.END_ELEMENT;
+import static javax.xml.stream.XMLStreamConstants.START_ELEMENT;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+import java.util.StringTokenizer;
+
+import javax.xml.XMLConstants;
+import javax.xml.namespace.NamespaceContext;
+import javax.xml.namespace.QName;
+import javax.xml.stream.XMLStreamConstants;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamReader;
+import javax.xml.stream.XMLStreamWriter;
+
+
+/**
+ * A base class with utility methods for the other artifact processors in this module. 
+ * 
+ * @version $Rev$ $Date$
+ */
+public abstract class BaseStAXArtifactProcessor {
+
+    /**
+     * Returns a QName from a string.  
+     * @param reader
+     * @param value
+     * @return
+     */
+    protected QName getQNameValue(XMLStreamReader reader, String value) {
+        if (value != null) {
+            int index = value.indexOf(':');
+            String prefix = index == -1 ? "" : value.substring(0, index);
+            String localName = index == -1 ? value : value.substring(index + 1);
+            String ns = reader.getNamespaceContext().getNamespaceURI(prefix);
+            if (ns == null) {
+                ns = "";
+            }
+            return new QName(ns, localName, prefix);
+        } else {
+            return null;
+        }
+    }
+
+    /**
+     * Returns the boolean value of an attribute.
+     * @param reader
+     * @param name
+     * @return
+     */
+    protected boolean getBoolean(XMLStreamReader reader, String name) {
+        String value = reader.getAttributeValue(null, name);
+        if (value == null) {
+            return false;
+        }
+        return Boolean.valueOf(value);
+    }
+
+    /**
+     * Returns the QName value of an attribute.
+     * @param reader
+     * @param name
+     * @return
+     */
+    protected QName getQName(XMLStreamReader reader, String name) {
+        String qname = reader.getAttributeValue(null, name);
+        return getQNameValue(reader, qname);
+    }
+
+    /**
+     * Returns the value of an attribute as a list of QNames.
+     * @param reader
+     * @param name
+     * @return
+     */
+    protected List<QName> getQNames(XMLStreamReader reader, String name) {
+        String value = reader.getAttributeValue(null, name);
+        if (value != null) {
+            List<QName> qnames = new ArrayList<QName>();
+            for (StringTokenizer tokens = new StringTokenizer(value); tokens.hasMoreTokens();) {
+                qnames.add(getQName(reader, tokens.nextToken()));
+            }
+            return qnames;
+        } else {
+            return Collections.emptyList();
+        }
+    }
+
+    /**
+     * Returns the string value of an attribute.
+     * @param reader
+     * @param name
+     * @return
+     */
+    protected String getString(XMLStreamReader reader, String name) {
+        return reader.getAttributeValue(null, name);
+    }
+
+    /**
+     * Test if an attribute is explicitly set
+     * @param reader
+     * @param name
+     * @return
+     */
+    protected boolean isSet(XMLStreamReader reader, String name) {
+        return reader.getAttributeValue(null, name) != null;
+    }
+
+    /**
+     * Returns the value of xsi:type attribute
+     * @param reader The XML stream reader
+     * @return The QName of the type, if the attribute is not present, null is
+     *         returned.
+     */
+    protected QName getXSIType(XMLStreamReader reader) {
+        String qname = reader.getAttributeValue(XMLConstants.W3C_XML_SCHEMA_INSTANCE_NS_URI, "type");
+        return getQNameValue(reader, qname);
+    }
+
+    /**
+     * Parse the next child element.
+     * @param reader
+     * @return
+     * @throws XMLStreamException
+     */
+    protected boolean nextChildElement(XMLStreamReader reader) throws XMLStreamException {
+        while (reader.hasNext()) {
+            int event = reader.next();
+            if (event == END_ELEMENT) {
+                return false;
+            }
+            if (event == START_ELEMENT) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Advance the stream to the next END_ELEMENT event skipping any nested
+     * content.
+     * @param reader the reader to advance
+     * @throws XMLStreamException if there was a problem reading the stream
+     */
+    protected void skipToEndElement(XMLStreamReader reader) throws XMLStreamException {
+        int depth = 0;
+        while (reader.hasNext()) {
+            int event = reader.next();
+            if (event == XMLStreamConstants.START_ELEMENT) {
+                depth++;
+            } else if (event == XMLStreamConstants.END_ELEMENT) {
+                if (depth == 0) {
+                    return;
+                }
+                depth--;
+            }
+        }
+    }
+    
+    /**
+     * 
+     * @param writer
+     * @param uri
+     * @throws XMLStreamException
+     */
+    private String writeElementPrefix(XMLStreamWriter writer, String uri) throws XMLStreamException {
+        if (uri == null) {
+            return null;
+        }
+        String prefix = writer.getPrefix(uri);
+        if (prefix != null) {
+            return null;
+        } else {
+            
+            // Find an available prefix and bind it to the given URI 
+            NamespaceContext nsc = writer.getNamespaceContext();
+            for (int i=1; ; i++) {
+                prefix = "ns" + i;
+                if (nsc.getNamespaceURI(prefix) == null) {
+                    break;
+                }
+            }
+            writer.setPrefix(prefix, uri);
+            return prefix;
+        }
+        
+    }
+
+    /**
+     * Start an element.
+     * @param uri
+     * @param name
+     * @param attrs
+     * @throws XMLStreamException
+     */
+    protected void writeStart(XMLStreamWriter writer, String uri, String name, XAttr... attrs) throws XMLStreamException {
+        String prefix = writeElementPrefix(writer, uri);
+        writer.writeStartElement(uri, name);
+        if (prefix != null){
+            writer.writeNamespace(prefix,uri); 
+        }
+        writeAttributePrefixes(writer, attrs);
+        writeAttributes(writer, attrs);
+    }
+    
+    /**
+     * Start an element.
+     * @param qname
+     * @param attrs
+     * @throws XMLStreamException
+     */
+    protected void writeStart(XMLStreamWriter writer, QName qname, XAttr... attrs) throws XMLStreamException {
+        writeStart(writer, qname.getNamespaceURI(), qname.getLocalPart(), attrs);
+    }
+    
+    /**
+     * End an element. 
+     * @param writer
+     * @throws XMLStreamException
+     */
+    protected void writeEnd(XMLStreamWriter writer) throws XMLStreamException {
+        writer.writeEndElement();
+    }
+
+    /**
+     * Start a document.
+     * @param writer
+     * @throws XMLStreamException
+     */
+    protected void writeStartDocument(XMLStreamWriter writer, String uri, String name, XAttr... attrs) throws XMLStreamException {
+        writer.writeStartDocument();
+        writer.setDefaultNamespace(uri);
+        writeStart(writer, uri, name, attrs);
+        writer.writeDefaultNamespace(uri);
+    }
+
+    /**
+     * Start a document.
+     * @param writer
+     * @param qname
+     * @param attrs
+     * @throws XMLStreamException
+     */
+    protected void writeStartDocument(XMLStreamWriter writer, QName qname, XAttr... attrs) throws XMLStreamException {
+        writeStartDocument(writer, qname.getNamespaceURI(), qname.getLocalPart(), attrs);
+    }
+
+    /**
+     * End a document.
+     * @param writer
+     * @throws XMLStreamException
+     */
+    protected void writeEndDocument(XMLStreamWriter writer) throws XMLStreamException {
+        writer.writeEndDocument();
+    }
+
+    /**
+     * Write attributes to the current element.
+     * @param writer
+     * @param attrs
+     * @throws XMLStreamException
+     */
+    protected void writeAttributes(XMLStreamWriter writer, XAttr... attrs) throws XMLStreamException {
+        for (XAttr attr : attrs) {
+            if (attr != null)
+                attr.write(writer);
+        }
+    }
+
+    /**
+     * Write attribute prefixes to the current element.
+     * @param writer
+     * @param attrs
+     * @throws XMLStreamException
+     */
+    protected void writeAttributePrefixes(XMLStreamWriter writer, XAttr... attrs) throws XMLStreamException {
+        for (XAttr attr : attrs) {
+            if (attr != null)
+                attr.writePrefix(writer);
+        }
+    }
+
+    /**
+     * Represents an XML attribute that needs to be written to a document.
+     */
+    public static class XAttr {
+        
+        private static final String SCA10_NS = "http://www.osoa.org/xmlns/sca/1.0";
+
+        private String uri = SCA10_NS;
+        private String name;
+        private Object value;
+
+        public XAttr(String uri, String name, String value) {
+            this.uri = uri;
+            this.name = name;
+            this.value = value;
+        }
+
+        public XAttr(String name, String value) {
+            this(null, name, value);
+        }
+
+        public XAttr(String uri, String name, List<?> values) {
+            this.uri = uri;
+            this.name = name;
+            this.value = values;
+        }
+
+        public XAttr(String name, List<?> values) {
+            this(null, name, values);
+        }
+
+        public XAttr(String uri, String name, Boolean value) {
+            this.uri = uri;
+            this.name = name;
+            this.value = value;
+        }
+
+        public XAttr(String name, Boolean value) {
+            this(null, name, value);
+        }
+
+        public XAttr(String uri, String name, Integer value) {
+            this.uri = uri;
+            this.name = name;
+            this.value = value;
+        }
+
+        public XAttr(String name, Integer value) {
+            this(null, name, value);
+        }
+
+        public XAttr(String uri, String name, Double value) {
+            this.uri = uri;
+            this.name = name;
+            this.value = value;
+        }
+
+        public XAttr(String name, Double value) {
+            this(null, name, value);
+        }
+
+        public XAttr(String uri, String name, QName value) {
+            this.uri = uri;
+            this.name = name;
+            this.value = value;
+        }
+
+        public XAttr(String name, QName value) {
+            this(null, name, value);
+        }
+
+        /**
+         * Writes a string from a QName and registers a prefix for its namespace.  
+         * @param reader
+         * @param value
+         * @return
+         */
+        private String writeQNameValue(XMLStreamWriter writer, QName qname) throws XMLStreamException {
+            if (qname != null) {
+                String prefix = qname.getPrefix();
+                String uri = qname.getNamespaceURI();
+                prefix = writer.getPrefix(uri);
+                if (prefix != null) {
+
+                    // Use the prefix already bound to the given URI
+                    if (prefix.length() > 0) {
+                        return prefix + ":" + qname.getLocalPart();
+                    } else {
+                        
+                        // Empty prefix, just return the local part of the given qname
+                        return qname.getLocalPart();
+                    }
+                    
+                } else {
+                    
+                    // Find an available prefix and bind it to the given URI 
+                    NamespaceContext nsc = writer.getNamespaceContext();
+                    for (int i=1; ; i++) {
+                        prefix = "ns" + i;
+                        if (nsc.getNamespaceURI(prefix) == null) {
+                            break;
+                        }
+                    }
+                    writer.setPrefix(prefix, uri);
+                    writer.writeNamespace(prefix, uri);
+                    return prefix + ":" + qname.getLocalPart();
+                }
+            } else {
+                return null;
+            }
+        }
+
+        /**
+         * Registers a prefix for the namespace of a QName.  
+         * @param reader
+         * @param value
+         * @return
+         */
+        private void writeQNamePrefix(XMLStreamWriter writer, QName qname) throws XMLStreamException {
+            if (qname != null) {
+                String prefix = qname.getPrefix();
+                String uri = qname.getNamespaceURI();
+                prefix = writer.getPrefix(uri);
+                if (prefix != null) {
+                    return;
+                } else {
+                    
+                    // Find an available prefix and bind it to the given URI 
+                    NamespaceContext nsc = writer.getNamespaceContext();
+                    for (int i=1; ; i++) {
+                        prefix = "ns" + i;
+                        if (nsc.getNamespaceURI(prefix) == null) {
+                            break;
+                        }
+                    }
+                    writer.setPrefix(prefix, uri);
+                    writer.writeNamespace(prefix, uri);
+                }
+            }
+        }
+
+        /**
+         * Write to document
+         * @param writer
+         * @throws XMLStreamException
+         */
+        public void write(XMLStreamWriter writer) throws XMLStreamException {
+            String str;
+            if (value instanceof QName) {
+                
+                // Write a QName
+                str = writeQNameValue(writer, (QName)value);
+                
+            } else if (value instanceof List) {
+                
+                // Write a list of values
+                List<?> values = (List<?>)value;
+                if (values.isEmpty()) {
+                    return;
+                }
+                StringBuffer buffer = new StringBuffer();
+                for (Object v: values) {
+                    if (v == null) {
+                        // Skip null values
+                        continue;
+                    }
+                    
+                    if (v instanceof XAttr) {
+                        // Write an XAttr value
+                        ((XAttr)v).write(writer);
+                        continue;
+                    }
+
+                    if (buffer.length() != 0) {
+                        buffer.append(' ');
+                    }
+                    if (v instanceof QName) {
+                        // Write a QName value
+                        buffer.append(writeQNameValue(writer, (QName)v));
+                    } else {
+                        // Write value as a string 
+                        buffer.append(String.valueOf(v));
+                    }
+                }
+                str = buffer.toString();
+                
+            } else {
+                
+                // Write a string
+                if (value == null) {
+                    return;
+                }
+                str = String.valueOf(value);
+            }
+            if (str.length() == 0) {
+                return;
+            }
+
+            // Write the attribute
+            if (uri != null && !uri.equals(SCA10_NS)) {
+                writer.writeAttribute(uri, name, str);
+            } else {
+                writer.writeAttribute(name,str);
+            }
+        }
+
+        /**
+         * Registers a prefix for the namespace of a QName or list of QNames 
+         * @param writer
+         * @throws XMLStreamException
+         */
+        public void writePrefix(XMLStreamWriter writer) throws XMLStreamException {
+            if (value instanceof QName) {
+                
+                // Write prefix for a single QName value
+                writeQNamePrefix(writer, (QName)value);
+                
+            } else if (value instanceof List) {
+                
+                // Write prefixes for a list of values
+                for (Object v: (List<?>)value) {
+                    if (v instanceof QName) {
+                        // Write prefix for a QName value
+                        writeQNamePrefix(writer, (QName)v);
+                        
+                    } else if (v instanceof XAttr) {
+                        // Write prefix for an XAttr value
+                        ((XAttr)v).writePrefix(writer);
+                    }
+                }
+            }
+        }
+    }
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionException.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionException.java
new file mode 100644
index 0000000000..3b99eba586
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionException.java
@@ -0,0 +1,45 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+/**
+ * Base class for exceptions raised by contribution services.
+ *
+ * @version $Rev$ $Date$
+ */
+public class ContributionException extends Exception {
+
+    private static final long serialVersionUID = 4432880414927652578L;
+
+    protected ContributionException() {
+        super();
+    }
+
+    protected ContributionException(String message) {
+        super(message);
+    }
+
+    protected ContributionException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public ContributionException(Throwable cause) {
+        super(cause);
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionReadException.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionReadException.java
new file mode 100644
index 0000000000..6fd7d0c91e
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionReadException.java
@@ -0,0 +1,95 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+
+/**
+ * Denotes an exception while reading artifacts inside an SCA contribution.
+ *
+ * @version $Rev$ $Date$
+ */
+public class ContributionReadException extends ContributionException {
+    public static final int UNDEFINED = -1;
+    private static final long serialVersionUID = -7459051598906813461L;
+    private String resourceURI;
+    private int line = UNDEFINED;
+    private int column = UNDEFINED;
+
+    public ContributionReadException(String message) {
+        super(message);
+    }
+
+    public ContributionReadException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public ContributionReadException(Throwable cause) {
+        super(cause);
+    }
+    
+    /**
+     * Returns the location of the resource that was being read.
+     *
+     * @return the location of the resource that was being read
+     */
+    public String getResourceURI() {
+        return resourceURI;
+    }
+
+    /**
+     * Sets the location of the resource that was being read.
+     *
+     * @param resourceURI the location of the resource that was being read
+     */
+    public void setResourceURI(String resourceURI) {
+        this.resourceURI = resourceURI;
+    }
+
+    /**
+     * Returns the line inside the resource that was being read.
+     * @return the line inside the resource that was being read
+     */
+    public int getLine() {
+        return line;
+    }
+
+    /**
+     * Sets the line inside the resource that was being read.
+     * @param line the line inside the resource that was being read
+     */
+    public void setLine(int line) {
+        this.line = line;
+    }
+
+    /**
+     * Returns the column inside the resource that was being read.
+     * @return the column inside the resource that was being read
+     */
+    public int getColumn() {
+        return column;
+    }
+
+    /**
+     * Sets the column inside the resource that was being read.
+     * @param column the column inside the resource that was being read
+     */
+    public void setColumn(int column) {
+        this.column = column;
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionResolveException.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionResolveException.java
new file mode 100644
index 0000000000..fe1a09d398
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionResolveException.java
@@ -0,0 +1,42 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+
+/**
+ * Denotes a problem while resolving models inside an SCA contribution.
+ *
+ * @version $Rev$ $Date$
+ */
+public class ContributionResolveException extends ContributionException {
+    private static final long serialVersionUID = -7459051598906813461L;
+
+    public ContributionResolveException(String message) {
+        super(message);
+    }
+
+    public ContributionResolveException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public ContributionResolveException(Throwable cause) {
+        super(cause);
+    }
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionRuntimeException.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionRuntimeException.java
new file mode 100644
index 0000000000..0039dd9f8b
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionRuntimeException.java
@@ -0,0 +1,44 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+/**
+ * Base class for runtime exceptions raised by contribution services.
+ *
+ * @version $Rev$ $Date$
+ */
+public class ContributionRuntimeException extends RuntimeException {
+    private static final long serialVersionUID = 7711215366287498896L;
+
+    protected ContributionRuntimeException() {
+        super();
+    }
+
+    protected ContributionRuntimeException(String message) {
+        super(message);
+    }
+
+    protected ContributionRuntimeException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public ContributionRuntimeException(Throwable cause) {
+        super(cause);
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionWriteException.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionWriteException.java
new file mode 100644
index 0000000000..286c9dc791
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ContributionWriteException.java
@@ -0,0 +1,62 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+
+
+/**
+ * Denotes an exception while writing artifacts inside an SCA contribution.
+ *
+ * @version $Rev$ $Date$
+ */
+public class ContributionWriteException extends ContributionException {
+    private static final long serialVersionUID = -7459051598906813461L;
+    private String resourceURI;
+
+    public ContributionWriteException(String message) {
+        super(message);
+    }
+
+    public ContributionWriteException(String message, Throwable cause) {
+        super(message, cause);
+    }
+
+    public ContributionWriteException(Throwable cause) {
+        super(cause);
+    }
+    
+    /**
+     * Returns the location of the resource that was being written.
+     *
+     * @return the location of the resource that was being written
+     */
+    public String getResourceURI() {
+        return resourceURI;
+    }
+
+    /**
+     * Sets the location of the resource that was being written.
+     *
+     * @param resourceURI the location of the resource that was being written
+     */
+    public void setResourceURI(String resourceURI) {
+        this.resourceURI = resourceURI;
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultArtifactProcessorExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultArtifactProcessorExtensionPoint.java
new file mode 100644
index 0000000000..3c67a8c550
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultArtifactProcessorExtensionPoint.java
@@ -0,0 +1,66 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * The default implementation of an artifact processor extension point.
+ * 
+ * @version $Rev$ $Date$
+ */
+abstract class DefaultArtifactProcessorExtensionPoint<P> {
+    protected final Map<Object, P> processorsByArtifactType = new HashMap<Object, P>();
+    protected final Map<Class<?>, P> processorsByModelType = new HashMap<Class<?>, P>();
+
+    /**
+     * Constructs a new loader registry.
+     */
+    DefaultArtifactProcessorExtensionPoint() {
+    }
+
+    /**
+     * Returns the processor associated with the given artifact type.
+     * 
+     * @param artifactType An artifact type
+     * @return The processor associated with the given artifact type
+     */
+    public P getProcessor(Object artifactType) {
+        return processorsByArtifactType.get(artifactType);
+    }
+
+    /**
+     * Returns the processor associated with the given model type.
+     * 
+     * @param modelType A model type
+     * @return The processor associated with the given model type
+     */
+    public P getProcessor(Class<?> modelType) {
+        Class<?>[] classes = modelType.getInterfaces();
+        for (Class<?> c : classes) {
+            P processor = processorsByModelType.get(c);
+            if (processor != null) {
+                return processor;
+            }
+        }
+        return processorsByModelType.get(modelType);
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultStAXArtifactProcessorExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultStAXArtifactProcessorExtensionPoint.java
new file mode 100644
index 0000000000..d268c5b011
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultStAXArtifactProcessorExtensionPoint.java
@@ -0,0 +1,384 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.io.IOException;
+import java.lang.reflect.Constructor;
+import java.util.Map;
+import java.util.Set;
+
+import javax.xml.namespace.QName;
+import javax.xml.stream.XMLInputFactory;
+import javax.xml.stream.XMLOutputFactory;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamReader;
+import javax.xml.stream.XMLStreamWriter;
+
+import org.apache.tuscany.sca.assembly.AssemblyFactory;
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.core.ExtensionPointRegistry;
+import org.apache.tuscany.sca.core.FactoryExtensionPoint;
+import org.apache.tuscany.sca.core.UtilityExtensionPoint;
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+import org.apache.tuscany.sca.monitor.Monitor;
+import org.apache.tuscany.sca.monitor.MonitorFactory;
+import org.apache.tuscany.sca.monitor.Problem;
+import org.apache.tuscany.sca.monitor.Problem.Severity;
+import org.apache.tuscany.sca.policy.PolicyFactory;
+
+/**
+ * The default implementation of an extension point for StAX artifact processors.
+ * 
+ * @version $Rev$ $Date$
+ */
+public class DefaultStAXArtifactProcessorExtensionPoint extends
+    DefaultArtifactProcessorExtensionPoint<StAXArtifactProcessor> implements StAXArtifactProcessorExtensionPoint {
+
+    private ExtensionPointRegistry extensionPoints;
+    private FactoryExtensionPoint modelFactories;
+    private MonitorFactory monitorFactory;
+    private boolean loaded;
+    private StAXArtifactProcessor<Object> extensibleStAXProcessor;
+    private StAXAttributeProcessor<Object> extensibleStAXAttributeProcessor;
+    private Monitor monitor = null;
+
+    /**
+     * Constructs a new extension point.
+     */
+    public DefaultStAXArtifactProcessorExtensionPoint(ExtensionPointRegistry extensionPoints) {
+        this.extensionPoints = extensionPoints;
+        this.modelFactories = extensionPoints.getExtensionPoint(FactoryExtensionPoint.class);
+        XMLInputFactory inputFactory = modelFactories.getFactory(XMLInputFactory.class);
+        XMLOutputFactory outputFactory = modelFactories.getFactory(XMLOutputFactory.class);
+        UtilityExtensionPoint utilities = this.extensionPoints.getExtensionPoint(UtilityExtensionPoint.class);
+        MonitorFactory monitorFactory = utilities.getUtility(MonitorFactory.class);
+        if (monitorFactory != null)
+        	this.monitor = monitorFactory.createMonitor();
+        this.extensibleStAXProcessor = new ExtensibleStAXArtifactProcessor(this, inputFactory, outputFactory, this.monitor);
+        
+        StAXAttributeProcessorExtensionPoint attributeExtensionPoint = extensionPoints.getExtensionPoint(StAXAttributeProcessorExtensionPoint.class);
+        this.extensibleStAXAttributeProcessor = new ExtensibleStAXAttributeProcessor(attributeExtensionPoint ,inputFactory, outputFactory, this.monitor);
+    }
+    
+    /**
+     * Report a exception.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+    */
+    private void error(String message, Object model, Exception ex) {
+        if (monitor != null) {
+    	    Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, ex);
+    	    monitor.problem(problem);
+    	}        
+    }
+
+    public void addArtifactProcessor(StAXArtifactProcessor artifactProcessor) {
+        if (artifactProcessor.getArtifactType() != null) {
+            processorsByArtifactType.put((Object)artifactProcessor.getArtifactType(), artifactProcessor);
+        }
+        if (artifactProcessor.getModelType() != null) {
+            processorsByModelType.put(artifactProcessor.getModelType(), artifactProcessor);
+        }
+    }
+
+    public void removeArtifactProcessor(StAXArtifactProcessor artifactProcessor) {
+        if (artifactProcessor.getArtifactType() != null) {
+            processorsByArtifactType.remove((Object)artifactProcessor.getArtifactType());
+        }
+        if (artifactProcessor.getModelType() != null) {
+            processorsByModelType.remove(artifactProcessor.getModelType());
+        }
+    }
+
+    @Override
+    public StAXArtifactProcessor getProcessor(Class<?> modelType) {
+        loadArtifactProcessors();
+        return super.getProcessor(modelType);
+    }
+
+    @Override
+    public StAXArtifactProcessor getProcessor(Object artifactType) {
+        loadArtifactProcessors();
+        return super.getProcessor(artifactType);
+    }
+
+    /**
+     * Returns a QName object from a QName expressed as {ns}name
+     * or ns#name.
+     * 
+     * @param qname
+     * @return
+     */
+    private static QName getQName(String qname) {
+        if (qname == null) {
+            return null;
+        }
+        qname = qname.trim();
+        if (qname.startsWith("{")) {
+            int h = qname.indexOf('}');
+            if (h != -1) {
+                return new QName(qname.substring(1, h), qname.substring(h + 1));
+            }
+        } else {
+            int h = qname.indexOf('#');
+            if (h != -1) {
+                return new QName(qname.substring(0, h), qname.substring(h + 1));
+            }
+        }
+        throw new IllegalArgumentException("Invalid qname: "+qname);
+    }
+
+    /**
+     * Lazily load artifact processors registered in the extension point.
+     */
+    private void loadArtifactProcessors() {
+        if (loaded)
+            return;
+
+        // Get the processor service declarations
+        Set<ServiceDeclaration> processorDeclarations;
+        try {
+            processorDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations(StAXArtifactProcessor.class.getName());
+        } catch (IOException e) {
+        	IllegalStateException ie = new IllegalStateException(e);
+        	error("IllegalStateException", extensibleStAXProcessor, ie);
+            throw ie;
+        }
+
+        for (ServiceDeclaration processorDeclaration : processorDeclarations) {
+            Map<String, String> attributes = processorDeclaration.getAttributes();
+
+            // Load a StAX artifact processor
+
+            // Get the model QName
+            QName artifactType = getQName(attributes.get("qname"));
+
+            // Get the model class name
+            String modelTypeName = attributes.get("model");
+
+            // Get the model factory class name 
+            String factoryName = attributes.get("factory");
+
+            // Create a processor wrapper and register it
+            StAXArtifactProcessor processor =
+                new LazyStAXArtifactProcessor(artifactType, modelTypeName, factoryName,
+                                              processorDeclaration, extensionPoints, modelFactories, 
+                                              extensibleStAXProcessor,extensibleStAXAttributeProcessor, monitor);
+            addArtifactProcessor(processor);
+        }
+
+        loaded = true;
+    }
+
+    /**
+     * A wrapper around an Artifact processor class allowing lazy loading and
+     * initialization of artifact processors.
+     */
+    private static class LazyStAXArtifactProcessor implements StAXArtifactProcessor {
+
+        private ExtensionPointRegistry extensionPoints;
+        private QName artifactType;
+        private String modelTypeName;
+        private String factoryName;
+        private ServiceDeclaration processorDeclaration;
+        private StAXArtifactProcessor processor;
+        private Class<?> modelType;
+        private StAXArtifactProcessor<Object> extensionProcessor;
+        private StAXAttributeProcessor<Object> extensionAttributeProcessor;
+        private Monitor monitor;
+
+        LazyStAXArtifactProcessor(QName artifactType,
+                                  String modelTypeName,
+                                  String factoryName,
+                                  ServiceDeclaration processorDeclaration,
+                                  ExtensionPointRegistry extensionPoints,
+                                  FactoryExtensionPoint modelFactories,
+                                  StAXArtifactProcessor<Object> extensionProcessor,
+                                  StAXAttributeProcessor<Object> extensionAttributeProcessor,
+                                  Monitor monitor) {
+
+            this.extensionPoints = extensionPoints;
+            this.artifactType = artifactType;
+            this.modelTypeName = modelTypeName;
+            this.factoryName = factoryName;
+            this.processorDeclaration = processorDeclaration;
+            this.extensionProcessor = extensionProcessor;
+            this.extensionAttributeProcessor = extensionAttributeProcessor;
+            this.monitor = monitor;
+        }
+
+        public QName getArtifactType() {
+            return artifactType;
+        }
+        
+        private void error(String message, Object model, Exception ex) {
+            if (monitor != null) {
+        	    Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, ex);
+        	    monitor.problem(problem);
+        	}        
+        }
+
+        @SuppressWarnings("unchecked")
+        private StAXArtifactProcessor getProcessor() {
+            if (processor == null) {
+
+                if (processorDeclaration.getClassName()
+                    .equals("org.apache.tuscany.sca.assembly.xml.DefaultBeanModelProcessor")) {
+
+                    // Specific initialization for the DefaultBeanModelProcessor
+                    FactoryExtensionPoint modelFactories = extensionPoints.getExtensionPoint(FactoryExtensionPoint.class);
+                    AssemblyFactory assemblyFactory = modelFactories.getFactory(AssemblyFactory.class);
+                    PolicyFactory policyFactory = modelFactories.getFactory(PolicyFactory.class);
+                    try {
+                        Class<StAXArtifactProcessor> processorClass =
+                            (Class<StAXArtifactProcessor>)processorDeclaration.loadClass();
+                        Object modelFactory;
+                        if (factoryName != null) {
+                            Class<?> factoryClass = (Class<?>)processorDeclaration.loadClass(factoryName);
+                            modelFactory = modelFactories.getFactory(factoryClass);
+                        } else {
+                            modelFactory = null;
+                        }
+                        Constructor<StAXArtifactProcessor> constructor =
+                            processorClass.getConstructor(AssemblyFactory.class,
+                                                          PolicyFactory.class,
+                                                          QName.class,
+                                                          Class.class,
+                                                          Object.class,
+                                                          Monitor.class);
+                        processor =
+                            constructor.newInstance(assemblyFactory,
+                                                    policyFactory,
+                                                    artifactType,
+                                                    getModelType(),
+                                                    modelFactory,
+                                                    monitor);
+                    } catch (Exception e) {
+                    	IllegalStateException ie = new IllegalStateException(e);
+                    	error("IllegalStateException", processor, ie);
+                        throw ie;
+                    }
+                } else {
+                    FactoryExtensionPoint modelFactories = extensionPoints.getExtensionPoint(FactoryExtensionPoint.class);
+
+                    // Load and instantiate the processor class
+                    try {
+                    	Class<StAXArtifactProcessor> processorClass =
+                    		(Class<StAXArtifactProcessor>)processorDeclaration.loadClass();
+                    	try {
+                    		Constructor<StAXArtifactProcessor> constructor =
+                    			processorClass.getConstructor(FactoryExtensionPoint.class, Monitor.class);
+                    		processor = constructor.newInstance(modelFactories, monitor);
+                    	} catch (NoSuchMethodException e) {
+                    		try {
+                    			Constructor<StAXArtifactProcessor> constructor =
+                    				processorClass.getConstructor(ExtensionPointRegistry.class, Monitor.class);
+                    			processor = constructor.newInstance(extensionPoints, monitor);
+                    		} catch (NoSuchMethodException e1) {
+                    			try {
+                    				Constructor<StAXArtifactProcessor> constructor =
+                    					processorClass.getConstructor(FactoryExtensionPoint.class, StAXArtifactProcessor.class, Monitor.class);
+                    				processor = constructor.newInstance(modelFactories, extensionProcessor, monitor);
+                    			} catch (NoSuchMethodException e2) {
+                    				try {
+                    					Constructor<StAXArtifactProcessor> constructor =
+                    						processorClass.getConstructor(FactoryExtensionPoint.class, StAXArtifactProcessor.class, StAXAttributeProcessor.class, Monitor.class);
+                    					processor = constructor.newInstance(modelFactories, extensionProcessor, extensionAttributeProcessor, monitor);
+                    				} catch (NoSuchMethodException e2a) {
+                    					try {
+                    						Constructor<StAXArtifactProcessor> constructor =
+                    							processorClass.getConstructor(ExtensionPointRegistry.class, StAXArtifactProcessor.class, Monitor.class);
+                    						processor = constructor.newInstance(extensionPoints, extensionProcessor, monitor);
+                    					} catch (NoSuchMethodException e3) {
+                    						try {
+                    							Constructor<StAXArtifactProcessor> constructor =
+                    								processorClass.getConstructor(ExtensionPointRegistry.class, StAXArtifactProcessor.class, StAXAttributeProcessor.class, Monitor.class);
+                    							processor = constructor.newInstance(extensionPoints, extensionProcessor, extensionAttributeProcessor, monitor);
+                    						} catch (NoSuchMethodException e3a) {
+
+                    							try {
+                    								Constructor<StAXArtifactProcessor> constructor =
+                    									processorClass.getConstructor(FactoryExtensionPoint.class);
+                    								processor = constructor.newInstance(modelFactories);
+                    							} catch (NoSuchMethodException e4) {
+                    								try {
+                    									Constructor<StAXArtifactProcessor> constructor =
+                    										processorClass.getConstructor(ExtensionPointRegistry.class);
+                    									processor = constructor.newInstance(extensionPoints);
+                    								} catch (NoSuchMethodException e4a) {
+                    									try {
+                    										Constructor<StAXArtifactProcessor> constructor =
+                    											processorClass.getConstructor(FactoryExtensionPoint.class, StAXArtifactProcessor.class);
+                    										processor = constructor.newInstance(modelFactories, extensionProcessor);
+                    									} catch (NoSuchMethodException e5) {
+                    										Constructor<StAXArtifactProcessor> constructor =
+                    											processorClass.getConstructor(ExtensionPointRegistry.class, StAXArtifactProcessor.class);
+                    										processor = constructor.newInstance(extensionPoints, extensionProcessor);
+                    									}
+                    								}
+                    							}
+                    						}
+                    					}
+                    				}
+                    			}
+                    		}
+                    	}
+                    } catch (Exception e) {
+                    	IllegalStateException ie = new IllegalStateException(e);
+                    	error("IllegalStateException", processor, ie);
+                        throw ie;
+                    }
+                }
+            }
+            return processor;
+        }
+
+        public Object read(XMLStreamReader inputSource) throws ContributionReadException, XMLStreamException {
+            return getProcessor().read(inputSource);
+        }
+
+        @SuppressWarnings("unchecked")
+        public void write(Object model, XMLStreamWriter outputSource) throws ContributionWriteException,
+            XMLStreamException {
+            getProcessor().write(model, outputSource);
+        }
+
+        public Class<?> getModelType() {
+            if (modelTypeName != null && modelType == null) {
+                try {
+                    modelType = processorDeclaration.loadClass(modelTypeName);
+                } catch (Exception e) {
+                	IllegalStateException ie = new IllegalStateException(e);
+                	error("IllegalStateException", processorDeclaration, ie);
+                    throw ie;
+                }
+            }
+            return modelType;
+        }
+
+        @SuppressWarnings("unchecked")
+        public void resolve(Object model, ModelResolver resolver) throws ContributionResolveException {
+            getProcessor().resolve(model, resolver);
+        }
+
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultStAXAttributeProcessorExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultStAXAttributeProcessorExtensionPoint.java
new file mode 100644
index 0000000000..bd38a609a6
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultStAXAttributeProcessorExtensionPoint.java
@@ -0,0 +1,323 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.io.IOException;
+import java.lang.reflect.Constructor;
+import java.util.Map;
+import java.util.Set;
+
+import javax.xml.namespace.QName;
+import javax.xml.stream.XMLInputFactory;
+import javax.xml.stream.XMLOutputFactory;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamReader;
+import javax.xml.stream.XMLStreamWriter;
+
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.core.ExtensionPointRegistry;
+import org.apache.tuscany.sca.core.FactoryExtensionPoint;
+import org.apache.tuscany.sca.core.UtilityExtensionPoint;
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+import org.apache.tuscany.sca.monitor.Monitor;
+import org.apache.tuscany.sca.monitor.MonitorFactory;
+import org.apache.tuscany.sca.monitor.Problem;
+import org.apache.tuscany.sca.monitor.Problem.Severity;
+
+/**
+ * The default implementation of an extension point for StAX artifact processors.
+ * 
+ * @version $Rev$ $Date$
+ */
+public class DefaultStAXAttributeProcessorExtensionPoint extends
+    DefaultArtifactProcessorExtensionPoint<StAXAttributeProcessor> implements StAXAttributeProcessorExtensionPoint {
+
+    private ExtensionPointRegistry extensionPoints;
+    private FactoryExtensionPoint modelFactories;
+    private StAXAttributeProcessor<Object> extensibleStAXAttributeProcessor;
+    private boolean loaded;
+    private Monitor monitor = null;
+
+    /**
+     * Constructs a new extension point.
+     */
+    public DefaultStAXAttributeProcessorExtensionPoint(ExtensionPointRegistry extensionPoints) {
+        this.extensionPoints = extensionPoints;
+        this.modelFactories = extensionPoints.getExtensionPoint(FactoryExtensionPoint.class);
+        XMLInputFactory inputFactory = modelFactories.getFactory(XMLInputFactory.class);
+        XMLOutputFactory outputFactory = modelFactories.getFactory(XMLOutputFactory.class);
+        UtilityExtensionPoint utilities = this.extensionPoints.getExtensionPoint(UtilityExtensionPoint.class);
+        MonitorFactory monitorFactory = utilities.getUtility(MonitorFactory.class);
+        if (monitorFactory != null) {
+        	this.monitor = monitorFactory.createMonitor();
+        }
+        this.extensibleStAXAttributeProcessor = new ExtensibleStAXAttributeProcessor(this, inputFactory, outputFactory, this.monitor);
+    }
+    
+    /**
+     * Report a exception.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+    */
+    private void error(String message, Object model, Exception ex) {
+        if (monitor != null) {
+    	    Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, ex);
+    	    monitor.problem(problem);
+    	}        
+    }
+
+    public void addArtifactProcessor(StAXAttributeProcessor artifactProcessor) {
+        if (artifactProcessor.getArtifactType() != null) {
+            processorsByArtifactType.put((Object)artifactProcessor.getArtifactType(), artifactProcessor);
+        }
+        if (artifactProcessor.getModelType() != null) {
+            processorsByModelType.put(artifactProcessor.getModelType(), artifactProcessor);
+        }
+    }
+
+    public void removeArtifactProcessor(StAXAttributeProcessor artifactProcessor) {
+        if (artifactProcessor.getArtifactType() != null) {
+            processorsByArtifactType.remove((Object)artifactProcessor.getArtifactType());
+        }
+        if (artifactProcessor.getModelType() != null) {
+            processorsByModelType.remove(artifactProcessor.getModelType());
+        }
+    }
+
+    @Override
+    public StAXAttributeProcessor getProcessor(Class<?> modelType) {
+        loadArtifactProcessors();
+        return super.getProcessor(modelType);
+    }
+
+    @Override
+    public StAXAttributeProcessor getProcessor(Object artifactType) {
+        loadArtifactProcessors();
+        return super.getProcessor(artifactType);
+    }
+
+    /**
+     * Returns a QName object from a QName expressed as {ns}name
+     * or ns#name.
+     * 
+     * @param qname
+     * @return
+     */
+    private static QName getQName(String qname) {
+        if (qname == null) {
+            return null;
+        }
+        qname = qname.trim();
+        if (qname.startsWith("{")) {
+            int h = qname.indexOf('}');
+            if (h != -1) {
+                return new QName(qname.substring(1, h), qname.substring(h + 1));
+            }
+        } else {
+            int h = qname.indexOf('#');
+            if (h != -1) {
+                return new QName(qname.substring(0, h), qname.substring(h + 1));
+            }
+        }
+        throw new IllegalArgumentException("Invalid qname: "+qname);
+    }
+
+    /**
+     * Lazily load artifact processors registered in the extension point.
+     */
+    private void loadArtifactProcessors() {
+        if (loaded)
+            return;
+
+        // Get the processor service declarations
+        Set<ServiceDeclaration> processorDeclarations;
+        try {
+            processorDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations(StAXAttributeProcessor.class.getName());
+        } catch (IOException e) {
+        	IllegalStateException ie = new IllegalStateException(e);
+        	error("IllegalStateException", extensibleStAXAttributeProcessor, ie);
+            throw ie;
+        }
+
+        for (ServiceDeclaration processorDeclaration : processorDeclarations) {
+            Map<String, String> attributes = processorDeclaration.getAttributes();
+
+            // Load a StAX artifact processor
+
+            // Get the model QName
+            QName artifactType = getQName(attributes.get("qname"));
+
+            // Get the model class name
+            String modelTypeName = attributes.get("model");
+
+            // Get the model factory class name 
+            String factoryName = attributes.get("factory");
+
+            // Create a processor wrapper and register it
+            StAXAttributeProcessor processor =
+                new LazyStAXAttributeProcessor(artifactType, modelTypeName, factoryName,
+                                              processorDeclaration, extensionPoints, modelFactories, 
+                                              extensibleStAXAttributeProcessor, monitor);
+            addArtifactProcessor(processor);
+        }
+
+        loaded = true;
+    }
+
+    /**
+     * A wrapper around an Artifact processor class allowing lazy loading and
+     * initialization of artifact processors.
+     */
+    private static class LazyStAXAttributeProcessor implements StAXAttributeProcessor {
+
+        private ExtensionPointRegistry extensionPoints;
+        private QName artifactType;
+        private String modelTypeName;
+        private String factoryName;
+        private ServiceDeclaration processorDeclaration;
+        private StAXAttributeProcessor processor;
+        private Class<?> modelType;
+        private StAXAttributeProcessor<Object> extensionProcessor;
+        private Monitor monitor;
+
+        LazyStAXAttributeProcessor(QName artifactType,
+                                  String modelTypeName,
+                                  String factoryName,
+                                  ServiceDeclaration processorDeclaration,
+                                  ExtensionPointRegistry extensionPoints,
+                                  FactoryExtensionPoint modelFactories,
+                                  StAXAttributeProcessor<Object> extensionProcessor,
+                                  Monitor monitor) {
+
+            this.extensionPoints = extensionPoints;
+            this.artifactType = artifactType;
+            this.modelTypeName = modelTypeName;
+            this.factoryName = factoryName;
+            this.processorDeclaration = processorDeclaration;
+            this.extensionProcessor = extensionProcessor;
+            this.monitor = monitor;
+        }
+
+        public QName getArtifactType() {
+            return artifactType;
+        }
+        
+        private void error(String message, Object model, Exception ex) {
+            if (monitor != null) {
+        	    Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, ex);
+        	    monitor.problem(problem);
+        	}        
+        }
+
+        @SuppressWarnings("unchecked")
+        private StAXAttributeProcessor getProcessor() {
+            if (processor == null) {
+                FactoryExtensionPoint modelFactories = extensionPoints.getExtensionPoint(FactoryExtensionPoint.class);
+
+                // Load and instantiate the processor class
+                try {
+                    Class<StAXAttributeProcessor> processorClass =
+                        (Class<StAXAttributeProcessor>)processorDeclaration.loadClass();
+                    try {
+                        Constructor<StAXAttributeProcessor> constructor =
+                            processorClass.getConstructor(FactoryExtensionPoint.class, Monitor.class);
+                        processor = constructor.newInstance(modelFactories, monitor);
+                    } catch (NoSuchMethodException e) {
+                      try {
+                          Constructor<StAXAttributeProcessor> constructor =
+                              processorClass.getConstructor(ExtensionPointRegistry.class, Monitor.class);
+                          processor = constructor.newInstance(extensionPoints, monitor);
+                      } catch (NoSuchMethodException e1) {
+                        try {
+                            Constructor<StAXAttributeProcessor> constructor =
+                                processorClass.getConstructor(FactoryExtensionPoint.class, StAXArtifactProcessor.class, Monitor.class);
+                            processor = constructor.newInstance(modelFactories, extensionProcessor, monitor);
+                        } catch (NoSuchMethodException e2) {
+                            try {
+                                Constructor<StAXAttributeProcessor> constructor =
+                                    processorClass.getConstructor(ExtensionPointRegistry.class, StAXArtifactProcessor.class, Monitor.class);
+                                processor = constructor.newInstance(extensionPoints, extensionProcessor, monitor);
+                            } catch (NoSuchMethodException e3) {
+                                try {
+                                    Constructor<StAXAttributeProcessor> constructor =
+                                        processorClass.getConstructor(FactoryExtensionPoint.class);
+                                    processor = constructor.newInstance(modelFactories);
+                                } catch (NoSuchMethodException e4) {
+                                  try {
+                                      Constructor<StAXAttributeProcessor> constructor =
+                                          processorClass.getConstructor(ExtensionPointRegistry.class);
+                                      processor = constructor.newInstance(extensionPoints);
+                                  } catch (NoSuchMethodException e4a) {
+                                    try {
+                                        Constructor<StAXAttributeProcessor> constructor =
+                                            processorClass.getConstructor(FactoryExtensionPoint.class, StAXArtifactProcessor.class);
+                                        processor = constructor.newInstance(modelFactories, extensionProcessor);
+                                    } catch (NoSuchMethodException e5) {
+                                        Constructor<StAXAttributeProcessor> constructor =
+                                            processorClass.getConstructor(ExtensionPointRegistry.class, StAXArtifactProcessor.class);
+                                        processor = constructor.newInstance(extensionPoints, extensionProcessor);
+                                    }
+                                  }
+                                }
+                            }
+                        }
+                      }
+                    }
+                } catch (Exception e) {
+                	IllegalStateException ie = new IllegalStateException(e);
+                	error("IllegalStateException", processor, ie);
+                    throw ie;
+                }
+
+            }
+            return processor;
+        }
+
+        public Object read(QName attributeName, XMLStreamReader inputSource) throws ContributionReadException, XMLStreamException {
+            return getProcessor().read(attributeName, inputSource);
+        }
+
+        @SuppressWarnings("unchecked")
+        public void write(Object model, XMLStreamWriter outputSource) throws ContributionWriteException, XMLStreamException {
+            getProcessor().write(model, outputSource);
+        }
+
+        public Class<?> getModelType() {
+            if (modelTypeName != null && modelType == null) {
+                try {
+                    modelType = processorDeclaration.loadClass(modelTypeName);
+                } catch (Exception e) {
+                	IllegalStateException ie = new IllegalStateException(e);
+                	error("IllegalStateException", processorDeclaration, ie);
+                    throw ie;
+                }
+            }
+            return modelType;
+        }
+
+        @SuppressWarnings("unchecked")
+        public void resolve(Object model, ModelResolver resolver) throws ContributionResolveException {
+            getProcessor().resolve(model, resolver);
+        }
+
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultURLArtifactProcessorExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultURLArtifactProcessorExtensionPoint.java
new file mode 100644
index 0000000000..402d4aa151
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultURLArtifactProcessorExtensionPoint.java
@@ -0,0 +1,239 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.io.IOException;
+import java.lang.reflect.Constructor;
+import java.net.URI;
+import java.net.URL;
+import java.util.Map;
+import java.util.Set;
+
+import javax.xml.stream.XMLInputFactory;
+import javax.xml.stream.XMLOutputFactory;
+
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.core.ExtensionPointRegistry;
+import org.apache.tuscany.sca.core.FactoryExtensionPoint;
+import org.apache.tuscany.sca.core.UtilityExtensionPoint;
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+import org.apache.tuscany.sca.monitor.Monitor;
+import org.apache.tuscany.sca.monitor.MonitorFactory;
+import org.apache.tuscany.sca.monitor.Problem;
+import org.apache.tuscany.sca.monitor.Problem.Severity;
+
+
+/**
+ * The default implementation of a URL artifact processor extension point.
+ * 
+ * @version $Rev$ $Date$
+ */
+public class DefaultURLArtifactProcessorExtensionPoint
+    extends DefaultArtifactProcessorExtensionPoint<URLArtifactProcessor>
+    implements URLArtifactProcessorExtensionPoint {
+    
+    private ExtensionPointRegistry extensionPoints;
+    private StAXArtifactProcessor<?> staxProcessor;
+    private boolean loaded;
+    private Monitor monitor = null;
+
+    /**
+     * Constructs a new extension point.
+     */
+    public DefaultURLArtifactProcessorExtensionPoint(ExtensionPointRegistry extensionPoints) {
+        this.extensionPoints = extensionPoints;
+        FactoryExtensionPoint modelFactories = this.extensionPoints.getExtensionPoint(FactoryExtensionPoint.class);
+        XMLInputFactory inputFactory = modelFactories.getFactory(XMLInputFactory.class);
+        XMLOutputFactory outputFactory = modelFactories.getFactory(XMLOutputFactory.class);
+        UtilityExtensionPoint utilities = this.extensionPoints.getExtensionPoint(UtilityExtensionPoint.class);
+        MonitorFactory monitorFactory = utilities.getUtility(MonitorFactory.class);
+        if (monitorFactory != null) 
+        	this.monitor = monitorFactory.createMonitor();
+        StAXArtifactProcessorExtensionPoint staxProcessors = extensionPoints.getExtensionPoint(StAXArtifactProcessorExtensionPoint.class);
+        staxProcessor = new ExtensibleStAXArtifactProcessor(staxProcessors, inputFactory, outputFactory, this.monitor);
+    }
+    
+    /**
+     * Report a exception.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+    */
+    private void error(String message, Object model, Exception ex) {
+        if (monitor != null) {
+    	    Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, ex);
+    	    monitor.problem(problem);
+    	}        
+    }
+    
+    public void addArtifactProcessor(URLArtifactProcessor artifactProcessor) {
+        if (artifactProcessor.getArtifactType() != null) {
+            processorsByArtifactType.put((Object)artifactProcessor.getArtifactType(), artifactProcessor);
+        }
+        if (artifactProcessor.getModelType() != null) {
+            processorsByModelType.put(artifactProcessor.getModelType(), artifactProcessor);
+        }
+    }
+    
+    public void removeArtifactProcessor(URLArtifactProcessor artifactProcessor) {
+        if (artifactProcessor.getArtifactType() != null) {
+            processorsByArtifactType.remove((Object)artifactProcessor.getArtifactType());
+        }
+        if (artifactProcessor.getModelType() != null) {
+            processorsByModelType.remove(artifactProcessor.getModelType());
+        }
+    }
+    
+    @Override
+    public URLArtifactProcessor getProcessor(Class<?> modelType) {
+        loadProcessors();
+        return super.getProcessor(modelType);
+    }
+    
+    @Override
+    public URLArtifactProcessor getProcessor(Object artifactType) {
+        loadProcessors();
+        return super.getProcessor(artifactType);
+    }
+
+    /**
+     * Lazily load artifact processors registered in the extension point.
+     */
+    private void loadProcessors() {
+        if (loaded)
+            return;
+
+        // Get the processor service declarations
+        Set<ServiceDeclaration> processorDeclarations; 
+        try {
+            processorDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations(URLArtifactProcessor.class.getName());
+        } catch (IOException e) {
+        	IllegalStateException ie = new IllegalStateException(e);
+        	error("IllegalStateException", staxProcessor, ie);
+            throw ie;
+        }
+        
+        for (ServiceDeclaration processorDeclaration: processorDeclarations) {
+            Map<String, String> attributes = processorDeclaration.getAttributes();
+            // Load a URL artifact processor
+            String artifactType = attributes.get("type");
+            String modelTypeName = attributes.get("model");
+            
+            // Create a processor wrapper and register it
+            URLArtifactProcessor processor = new LazyURLArtifactProcessor(artifactType, modelTypeName, 
+            		processorDeclaration, extensionPoints, staxProcessor, monitor);
+            addArtifactProcessor(processor);
+        }
+        
+        loaded = true;
+    }
+
+    /**
+     * A wrapper around an Artifact processor class allowing lazy loading and
+     * initialization of artifact processors.
+     */
+    private static class LazyURLArtifactProcessor implements URLArtifactProcessor {
+
+        private ExtensionPointRegistry extensionPoints;
+        private String artifactType;
+        private String modelTypeName;
+        private ServiceDeclaration processorDeclaration;
+        private URLArtifactProcessor processor;
+        private Class<?> modelType;
+        private StAXArtifactProcessor<?> staxProcessor;
+        private Monitor monitor;
+        
+        LazyURLArtifactProcessor(String artifactType, 
+        		String modelTypeName, 
+        		ServiceDeclaration processorDeclaration,
+        		ExtensionPointRegistry extensionPoints, 
+                        StAXArtifactProcessor<?> staxProcessor,
+                        Monitor monitor) {
+            this.artifactType = artifactType;
+            this.modelTypeName = modelTypeName;
+            this.processorDeclaration = processorDeclaration;
+            this.extensionPoints = extensionPoints;
+            this.staxProcessor = staxProcessor;
+            this.monitor = monitor;
+        }
+
+        public String getArtifactType() {
+            return artifactType;
+        }
+        
+        private void error(String message, Object model, Exception ex) {
+            if (monitor != null) {
+        	    Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, ex);
+        	    monitor.problem(problem);
+        	}        
+        }
+        
+        @SuppressWarnings("unchecked")
+        private URLArtifactProcessor getProcessor() {
+            if (processor == null) {
+                try {
+                    FactoryExtensionPoint modelFactories = extensionPoints.getExtensionPoint(FactoryExtensionPoint.class);
+                    Class<URLArtifactProcessor> processorClass = (Class<URLArtifactProcessor>)processorDeclaration.loadClass();
+                    try {
+                        Constructor<URLArtifactProcessor> constructor = processorClass.getConstructor(FactoryExtensionPoint.class, Monitor.class);
+                        processor = constructor.newInstance(modelFactories, monitor);
+                    } catch (NoSuchMethodException e) {
+                        try {
+                            Constructor<URLArtifactProcessor> constructor = processorClass.getConstructor(FactoryExtensionPoint.class, StAXArtifactProcessor.class, Monitor.class);
+                            processor = constructor.newInstance(modelFactories, staxProcessor, monitor);
+                        } catch (NoSuchMethodException e2) {
+                            Constructor<URLArtifactProcessor> constructor = processorClass.getConstructor(ExtensionPointRegistry.class, StAXArtifactProcessor.class, Monitor.class);
+                            processor = constructor.newInstance(extensionPoints, staxProcessor, monitor);
+                        }
+                    }
+                } catch (Exception e) {
+                	IllegalStateException ie = new IllegalStateException(e);
+                	error("IllegalStateException", processor, ie);
+                    throw ie;
+                }
+            }
+            return processor;
+        }
+
+        public Object read(URL contributionURL, URI artifactURI, URL artifactURL) throws ContributionReadException {
+            return getProcessor().read(contributionURL, artifactURI, artifactURL);
+        }
+        
+        public Class<?> getModelType() {
+            if (modelTypeName != null && modelType == null) {
+                try {
+                    modelType = processorDeclaration.loadClass(modelTypeName);
+                } catch (ClassNotFoundException e) {
+                	IllegalStateException ie = new IllegalStateException(e);
+                	error("IllegalStateException", processorDeclaration, ie);
+                    throw ie;
+                }
+            }
+            return modelType;
+        }
+
+        @SuppressWarnings("unchecked")
+        public void resolve(Object model, ModelResolver resolver) throws ContributionResolveException {
+            getProcessor().resolve(model, resolver);
+        }
+
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultValidatingXMLInputFactory.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultValidatingXMLInputFactory.java
new file mode 100644
index 0000000000..9258a837d8
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultValidatingXMLInputFactory.java
@@ -0,0 +1,325 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.Reader;
+import java.net.URL;
+import java.net.URLConnection;
+import java.security.AccessController;
+import java.security.PrivilegedActionException;
+import java.security.PrivilegedExceptionAction;
+import java.util.List;
+
+import javax.xml.XMLConstants;
+import javax.xml.stream.EventFilter;
+import javax.xml.stream.StreamFilter;
+import javax.xml.stream.XMLEventReader;
+import javax.xml.stream.XMLInputFactory;
+import javax.xml.stream.XMLReporter;
+import javax.xml.stream.XMLResolver;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamReader;
+import javax.xml.stream.util.XMLEventAllocator;
+import javax.xml.transform.Source;
+import javax.xml.transform.stream.StreamSource;
+import javax.xml.validation.Schema;
+import javax.xml.validation.SchemaFactory;
+
+import org.apache.tuscany.sca.core.ExtensionPointRegistry;
+import org.apache.tuscany.sca.core.FactoryExtensionPoint;
+import org.apache.tuscany.sca.core.UtilityExtensionPoint;
+import org.apache.tuscany.sca.monitor.Monitor;
+import org.apache.tuscany.sca.monitor.MonitorFactory;
+import org.apache.tuscany.sca.monitor.Problem;
+import org.apache.tuscany.sca.monitor.Problem.Severity;
+import org.xml.sax.SAXException;
+import org.xml.sax.SAXParseException;
+
+/**
+ * Default implementation of an XMLInputFactory that creates validating
+ * XMLStreamReaders.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultValidatingXMLInputFactory extends ValidatingXMLInputFactory {
+    
+    private XMLInputFactory inputFactory;
+    private ValidationSchemaExtensionPoint schemas;
+    private Monitor monitor;
+    private boolean initialized;
+    private boolean hasSchemas;
+    private Schema aggregatedSchema;
+
+    public DefaultValidatingXMLInputFactory(ExtensionPointRegistry registry) {
+        FactoryExtensionPoint factoryExtensionPoint = registry.getExtensionPoint(FactoryExtensionPoint.class);
+        XMLInputFactory factory = factoryExtensionPoint.getFactory(XMLInputFactory.class);
+        this.inputFactory = factory;
+        this.schemas = registry.getExtensionPoint(ValidationSchemaExtensionPoint.class);
+        this.monitor =
+            registry.getExtensionPoint(UtilityExtensionPoint.class).getUtility(MonitorFactory.class).createMonitor();
+    }
+    
+    /**
+     * Constructs a new XMLInputFactory.
+     * 
+     * @param inputFactory
+     * @param schemas
+     */
+    public DefaultValidatingXMLInputFactory(XMLInputFactory inputFactory, ValidationSchemaExtensionPoint schemas, Monitor monitor) {
+        this.inputFactory = inputFactory;
+        this.schemas = schemas;
+        this.monitor = monitor;
+    }
+    
+    /**
+     * Report a exception.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+     */
+     private void error(String message, Object model, Exception ex) {
+    	 if (monitor != null) {
+    		 Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, ex);
+    	     monitor.problem(problem);
+    	 }        
+     }
+    
+    /**
+     * Initialize the registered schemas and create an aggregated schema for
+     * validation.
+     */
+    private void initializeSchemas() {
+        if (initialized) {
+            return;
+        }
+        initialized = true;
+        
+        // Load the XSDs registered in the validation schema extension point
+        try {
+            List<String> uris = schemas.getSchemas();
+            int n = uris.size();
+            if (n ==0) {
+                return;
+            } else {
+                hasSchemas = true;
+            }
+            final Source[] sources = new Source[n];
+            for (int i =0; i < n; i++) {
+                final String uri = uris.get(i);
+                // Allow privileged access to open URL stream. Requires FilePermission in security policy.
+                final URL url = new URL( uri );
+                InputStream urlStream;
+                try {
+                    urlStream = AccessController.doPrivileged(new PrivilegedExceptionAction<InputStream>() {
+                        public InputStream run() throws IOException {
+                            URLConnection connection = url.openConnection();
+                            connection.setUseCaches(false);
+                            return connection.getInputStream();
+                        }
+                    });
+                } catch (PrivilegedActionException e) {
+                	error("PrivilegedActionException", url, (IOException)e.getException());
+                    throw (IOException)e.getException();
+                }
+                sources[i] = new StreamSource(urlStream, uri);
+            }
+            
+            // Create an aggregated validation schemas from all the XSDs
+            final SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
+            // Allow privileged access to check files. Requires FilePermission
+            // in security policy.
+            try {
+                aggregatedSchema = AccessController.doPrivileged(new PrivilegedExceptionAction<Schema>() {
+                    public Schema run() throws SAXException {
+                        return schemaFactory.newSchema(sources);
+                    }
+                });
+            } catch (PrivilegedActionException e) {
+            	error("PrivilegedActionException", schemaFactory, (SAXException)e.getException());
+                throw (SAXException)e.getException();
+            }
+
+        } catch (Error e) {
+            // FIXME Log this, some old JDKs don't support XMLSchema validation
+            //e.printStackTrace();
+        } catch (SAXParseException e) {
+        	IllegalStateException ie = new IllegalStateException(e);
+        	error("IllegalStateException", schemas, ie);
+            throw ie;
+        } catch (Exception e) {
+            //FIXME Log this, some old JDKs don't support XMLSchema validation
+            e.printStackTrace();
+        }
+    }
+
+    @Override
+    public XMLEventReader createFilteredReader(XMLEventReader arg0, EventFilter arg1) throws XMLStreamException {
+        return inputFactory.createFilteredReader(arg0, arg1);
+    }
+
+    @Override
+    public XMLStreamReader createFilteredReader(XMLStreamReader arg0, StreamFilter arg1) throws XMLStreamException {
+        return inputFactory.createFilteredReader(arg0, arg1);
+    }
+
+    @Override
+    public XMLEventReader createXMLEventReader(InputStream arg0, String arg1) throws XMLStreamException {
+        return inputFactory.createXMLEventReader(arg0, arg1);
+    }
+
+    @Override
+    public XMLEventReader createXMLEventReader(InputStream arg0) throws XMLStreamException {
+        return inputFactory.createXMLEventReader(arg0);
+    }
+
+    @Override
+    public XMLEventReader createXMLEventReader(Reader arg0) throws XMLStreamException {
+        return inputFactory.createXMLEventReader(arg0);
+    }
+
+    @Override
+    public XMLEventReader createXMLEventReader(Source arg0) throws XMLStreamException {
+        return inputFactory.createXMLEventReader(arg0);
+    }
+
+    @Override
+    public XMLEventReader createXMLEventReader(String arg0, InputStream arg1) throws XMLStreamException {
+        return inputFactory.createXMLEventReader(arg0, arg1);
+    }
+
+    @Override
+    public XMLEventReader createXMLEventReader(String arg0, Reader arg1) throws XMLStreamException {
+        return inputFactory.createXMLEventReader(arg0, arg1);
+    }
+
+    @Override
+    public XMLEventReader createXMLEventReader(XMLStreamReader arg0) throws XMLStreamException {
+        return inputFactory.createXMLEventReader(arg0);
+    }
+
+    @Override
+    public XMLStreamReader createXMLStreamReader(InputStream arg0, String arg1) throws XMLStreamException {
+        initializeSchemas();
+        if (hasSchemas) {
+            return new ValidatingXMLStreamReader(inputFactory.createXMLStreamReader(arg0, arg1), aggregatedSchema, monitor);
+        }else {
+            return inputFactory.createXMLStreamReader(arg0, arg1);
+        }
+    }
+
+    @Override
+    public XMLStreamReader createXMLStreamReader(InputStream arg0) throws XMLStreamException {
+        initializeSchemas();
+        if (hasSchemas) {
+            return new ValidatingXMLStreamReader(inputFactory.createXMLStreamReader(arg0), aggregatedSchema, monitor);
+        } else {
+            return inputFactory.createXMLStreamReader(arg0);
+        }
+    }
+
+    @Override
+    public XMLStreamReader createXMLStreamReader(Reader arg0) throws XMLStreamException {
+        initializeSchemas();
+        if (hasSchemas) {
+            return new ValidatingXMLStreamReader(inputFactory.createXMLStreamReader(arg0), aggregatedSchema, monitor);
+        } else {
+            return inputFactory.createXMLStreamReader(arg0);
+        }
+    }
+
+    @Override
+    public XMLStreamReader createXMLStreamReader(Source arg0) throws XMLStreamException {
+        initializeSchemas();
+        if (hasSchemas) {
+            return new ValidatingXMLStreamReader(inputFactory.createXMLStreamReader(arg0), aggregatedSchema, monitor);
+        } else {
+            return inputFactory.createXMLStreamReader(arg0);
+        }
+    }
+
+    @Override
+    public XMLStreamReader createXMLStreamReader(String arg0, InputStream arg1) throws XMLStreamException {
+        initializeSchemas();
+        if (hasSchemas) {
+            return new ValidatingXMLStreamReader(inputFactory.createXMLStreamReader(arg0, arg1), aggregatedSchema, monitor);
+        } else {
+            return inputFactory.createXMLStreamReader(arg0, arg1);
+        }
+    }
+
+    @Override
+    public XMLStreamReader createXMLStreamReader(String arg0, Reader arg1) throws XMLStreamException {
+        initializeSchemas();
+        if (hasSchemas) {
+            return new ValidatingXMLStreamReader(inputFactory.createXMLStreamReader(arg0, arg1), aggregatedSchema, monitor);
+        } else {
+            return inputFactory.createXMLStreamReader(arg0, arg1);
+        }
+    }
+
+    @Override
+    public XMLEventAllocator getEventAllocator() {
+        return inputFactory.getEventAllocator();
+    }
+
+    @Override
+    public Object getProperty(String arg0) throws IllegalArgumentException {
+        return inputFactory.getProperty(arg0);
+    }
+
+    @Override
+    public XMLReporter getXMLReporter() {
+        return inputFactory.getXMLReporter();
+    }
+
+    @Override
+    public XMLResolver getXMLResolver() {
+        return inputFactory.getXMLResolver();
+    }
+
+    @Override
+    public boolean isPropertySupported(String arg0) {
+        return inputFactory.isPropertySupported(arg0);
+    }
+
+    @Override
+    public void setEventAllocator(XMLEventAllocator arg0) {
+        inputFactory.setEventAllocator(arg0);
+    }
+
+    @Override
+    public void setProperty(String arg0, Object arg1) throws IllegalArgumentException {
+        inputFactory.setProperty(arg0, arg1);
+    }
+
+    @Override
+    public void setXMLReporter(XMLReporter arg0) {
+        inputFactory.setXMLReporter(arg0);
+    }
+
+    @Override
+    public void setXMLResolver(XMLResolver arg0) {
+        inputFactory.setXMLResolver(arg0);
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultValidationSchemaExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultValidationSchemaExtensionPoint.java
new file mode 100644
index 0000000000..a6631f498e
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/DefaultValidationSchemaExtensionPoint.java
@@ -0,0 +1,95 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Set;
+
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+
+/**
+ * Default implementation of an extension point for XML schemas. 
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultValidationSchemaExtensionPoint implements ValidationSchemaExtensionPoint {
+    
+    private List<String> schemas = new ArrayList<String>();
+    private boolean loaded;
+    
+    public void addSchema(String uri) {
+        schemas.add(uri);
+    }
+    
+    public void removeSchema(String uri) {
+        schemas.remove(uri);
+    }
+    
+    /**
+     * Load schema declarations from META-INF/services/
+     * org.apache.tuscany.sca.contribution.processor.ValidationSchema files
+     */
+    private void loadSchemas() {
+        if (loaded)
+            return;
+
+        // Get the schema declarations
+        Set<ServiceDeclaration> schemaDeclarations; 
+        try {
+            schemaDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations("org.apache.tuscany.sca.contribution.processor.ValidationSchema");
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }      
+        
+        // TODO - temp fix to ensure that the schema tuscany-sca.xsd always comes first
+        String tuscanyScaXsd = null;
+        
+        // Find each schema
+        for (ServiceDeclaration schemaDeclaration: schemaDeclarations) {
+            URL url = schemaDeclaration.getResource(schemaDeclaration.getClassName());
+            if (url == null) {
+                throw new IllegalArgumentException(new FileNotFoundException(schemaDeclaration.getClassName()));
+            }
+            
+            if (url.toString().contains("tuscany-sca.xsd")){
+                tuscanyScaXsd = url.toString();
+            } else {
+                schemas.add(url.toString());
+            }
+        }
+        
+        if (tuscanyScaXsd != null){
+            schemas.add(0, tuscanyScaXsd);
+        }
+        
+        loaded = true;
+    }
+    
+    public List<String> getSchemas() {
+        loadSchemas();
+        return schemas;
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ExtensibleStAXArtifactProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ExtensibleStAXArtifactProcessor.java
new file mode 100644
index 0000000000..947fdb330d
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ExtensibleStAXArtifactProcessor.java
@@ -0,0 +1,266 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import javax.xml.namespace.QName;
+import javax.xml.stream.Location;
+import javax.xml.stream.XMLInputFactory;
+import javax.xml.stream.XMLOutputFactory;
+import javax.xml.stream.XMLStreamConstants;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamReader;
+import javax.xml.stream.XMLStreamWriter;
+
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.monitor.Monitor;
+import org.apache.tuscany.sca.monitor.Problem;
+import org.apache.tuscany.sca.monitor.Problem.Severity;
+
+/**
+ * Implementation of an extensible StAX artifact processor.
+ * 
+ * Takes a StAXArtifactProcessorExtensionPoint and delegates to the proper
+ * StAXArtifactProcessor by element QName
+ * 
+ * @version $Rev$ $Date$
+ */
+public class ExtensibleStAXArtifactProcessor implements StAXArtifactProcessor<Object> {
+    private static final Logger logger = Logger.getLogger(ExtensibleStAXArtifactProcessor.class.getName()); 
+	
+    private static final QName ANY_ELEMENT = new QName("http://www.w3.org/2001/XMLSchema", "anyElement");
+
+    private XMLInputFactory inputFactory;
+    private XMLOutputFactory outputFactory;
+    private StAXArtifactProcessorExtensionPoint processors;
+    private Monitor monitor;
+
+    /**
+     * Constructs a new ExtensibleStAXArtifactProcessor.
+     * @param processors
+     * @param inputFactory
+     * @param outputFactory
+     */
+    public ExtensibleStAXArtifactProcessor(StAXArtifactProcessorExtensionPoint processors, 
+    									   XMLInputFactory inputFactory, 
+    									   XMLOutputFactory outputFactory,
+    									   Monitor monitor) {
+        super();
+        this.processors = processors;
+        this.inputFactory = inputFactory;
+        this.outputFactory = outputFactory;
+        if (this.outputFactory != null) {
+            this.outputFactory.setProperty("javax.xml.stream.isRepairingNamespaces", Boolean.TRUE);
+        }
+        this.monitor = monitor;
+    }
+    
+    /**
+     * Report a warning.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+     */
+     private void warning(String message, Object model, Object... messageParameters) {
+    	 if (monitor != null) {
+	        Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.WARNING, model, message, (Object[])messageParameters);
+	        monitor.problem(problem);
+    	 }
+     }
+     
+     /**
+      * Report a error.
+      * 
+      * @param problems
+      * @param message
+      * @param model
+      */
+     private void error(String message, Object model, Object... messageParameters) {
+     	if (monitor != null) {
+ 	        Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, (Object[])messageParameters);
+ 	        monitor.problem(problem);
+     	}
+     }
+    
+    /**
+     * Report a exception.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+     */
+     private void error(String message, Object model, Exception ex) {
+    	 if (monitor != null) {
+    		 Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, ex);
+    	     monitor.problem(problem);
+    	 }        
+     }
+
+
+    public Object read(XMLStreamReader source) throws ContributionReadException, XMLStreamException {
+        
+        // Delegate to the processor associated with the element QName
+        int event = source.getEventType();
+        if (event == XMLStreamConstants.START_DOCUMENT) {
+            source.nextTag();
+        }
+        QName name = source.getName();
+        StAXArtifactProcessor<?> processor = (StAXArtifactProcessor<?>)processors.getProcessor(name);
+        if (processor == null) {
+        	Location location = source.getLocation();
+            if (logger.isLoggable(Level.WARNING)) {                
+                logger.warning("Element " + name + " cannot be processed. (" + location + ")");
+            }
+            warning("ElementCannotBeProcessed", processors, name, location);
+            
+            return null;
+            
+            //FIXME Re-enable feature after complete merge is done
+            /*
+            StAXArtifactProcessor<?> anyElementProcessor = processors.getProcessor(ANY_ELEMENT);
+            if (anyElementProcessor != null) {
+                return anyElementProcessor.read(source);
+            } else {
+                return null;
+            }
+            */
+        }
+        return processor.read(source);
+    }
+    
+    @SuppressWarnings("unchecked")
+    public void write(Object model, XMLStreamWriter outputSource) throws ContributionWriteException, XMLStreamException {
+        
+        // Delegate to the processor associated with the model type
+        if (model != null) {
+            StAXArtifactProcessor processor = processors.getProcessor(model.getClass());
+            if (processor != null) {
+                processor.write(model, outputSource);
+            } else {
+                if (logger.isLoggable(Level.WARNING)) {
+                    logger.warning("No StAX processor is configured to handle " + model.getClass());
+                }
+                warning("NoStaxProcessor", processors, model.getClass());
+                
+                //FIXME Re-enable feature after complete merge is done
+                /*
+                StAXArtifactProcessor anyElementProcessor = processors.getProcessor(ANY_ELEMENT);
+                if (anyElementProcessor != null) {
+                    anyElementProcessor.write(model, outputSource);
+                }
+                */
+            }
+        }
+    }
+    
+    @SuppressWarnings("unchecked")
+    public void resolve(Object model, ModelResolver resolver) throws ContributionResolveException {
+
+        // Delegate to the processor associated with the model type
+        if (model != null) {
+            StAXArtifactProcessor processor = processors.getProcessor(model.getClass());
+            if (processor != null) {
+                processor.resolve(model, resolver);
+            }
+        }
+    }
+    
+    /**
+     * Read a model from an InputStream.
+     * @param is The artifact InputStream
+     * @param type Model type
+     * @return The model
+     * @throws ContributionReadException
+     */
+    public <M> M read(InputStream is, Class<M> type) throws ContributionReadException {
+        try {
+            XMLStreamReader reader;
+            try {
+                reader = inputFactory.createXMLStreamReader(is);
+                try {
+                    reader.nextTag();
+                    QName name = reader.getName();
+                    Object mo = read(reader);
+                    if (type.isInstance(mo)) {
+                        return type.cast(mo);
+                    } else {
+                    	error("UnrecognizedElementException", reader, name);
+                        UnrecognizedElementException e = new UnrecognizedElementException(name);                        
+                        throw e;
+                    }
+                } catch (ContributionReadException e) {
+                    Location location = reader.getLocation();
+                    e.setLine(location.getLineNumber());
+                    e.setColumn(location.getColumnNumber());
+                    error("ContributionReadException", reader, e);
+                    throw e;
+                } finally {
+                    try {
+                        reader.close();
+                    } catch (XMLStreamException e) {
+                        // ignore
+                    }
+                }
+            } finally {
+                try {
+                    is.close();
+                } catch (IOException e) {
+                    // ignore
+                }
+            }
+        } catch (XMLStreamException e) {
+            ContributionReadException ce = new ContributionReadException(e);
+            error("ContributionReadException", inputFactory, ce);
+            throw ce;
+        }
+    }
+
+    /**
+     * Write a model to an OutputStream.
+     * @param model
+     * @param os
+     * @throws ContributionWriteException
+     */
+    public void write(Object model, OutputStream os) throws ContributionWriteException {
+        try {
+            XMLStreamWriter writer = outputFactory.createXMLStreamWriter(os);
+            write(model, writer);
+            writer.flush();
+            writer.close();
+        } catch (XMLStreamException e) {
+        	ContributionWriteException cw = new ContributionWriteException(e);
+        	error("ContributionWriteException", outputFactory, cw);
+            throw cw;
+        }
+    }
+
+    public QName getArtifactType() {
+        return null;
+    }
+    
+    public Class<Object> getModelType() {
+        return null;
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ExtensibleStAXAttributeProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ExtensibleStAXAttributeProcessor.java
new file mode 100644
index 0000000000..48e80a073a
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ExtensibleStAXAttributeProcessor.java
@@ -0,0 +1,243 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import javax.xml.namespace.QName;
+import javax.xml.stream.Location;
+import javax.xml.stream.XMLInputFactory;
+import javax.xml.stream.XMLOutputFactory;
+import javax.xml.stream.XMLStreamConstants;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamReader;
+import javax.xml.stream.XMLStreamWriter;
+
+import org.apache.tuscany.sca.contribution.Constants;
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.monitor.Monitor;
+import org.apache.tuscany.sca.monitor.Problem;
+import org.apache.tuscany.sca.monitor.Problem.Severity;
+
+/**
+ * Implementation of an extensible StAX attribute processor.
+ * 
+ * Takes a StAXAttributeProcessorExtensionPoint and delegates to the proper
+ * StAXAttributeProcessor by attribute QName
+ * 
+ * @version $Rev$ $Date$
+ */
+public class ExtensibleStAXAttributeProcessor
+    implements StAXAttributeProcessor<Object> {
+
+    private static final Logger logger = Logger.getLogger(ExtensibleStAXAttributeProcessor.class.getName()); 
+    
+    private static final QName UNKNOWN_ATTRIBUTE = new QName(Constants.SCA10_TUSCANY_NS, "unknown");
+    
+    private XMLInputFactory inputFactory;
+    private XMLOutputFactory outputFactory;
+    private StAXAttributeProcessorExtensionPoint processors;
+    private Monitor monitor;
+
+    /**
+     * Constructs a new ExtensibleStAXArtifactProcessor.
+     * @param processors
+     * @param inputFactory
+     * @param outputFactory
+     */
+    public ExtensibleStAXAttributeProcessor(StAXAttributeProcessorExtensionPoint processors, 
+    									   XMLInputFactory inputFactory, 
+    									   XMLOutputFactory outputFactory,
+    									   Monitor monitor) {
+        super();
+        this.processors = processors;
+        this.inputFactory = inputFactory;
+        this.outputFactory = outputFactory;
+        if (this.outputFactory != null) {
+            this.outputFactory.setProperty("javax.xml.stream.isRepairingNamespaces", Boolean.TRUE);
+        }
+        this.monitor = monitor;
+    }
+    
+    /**
+     * Report a warning.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+     */
+     private void warning(String message, Object model, Object... messageParameters) {
+    	 if (monitor != null) {
+	        Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.WARNING, model, message, (Object[])messageParameters);
+	        monitor.problem(problem);
+    	 }
+     }
+     
+     /**
+      * Report a error.
+      * 
+      * @param problems
+      * @param message
+      * @param model
+      */
+     private void error(String message, Object model, Object... messageParameters) {
+     	if (monitor != null) {
+ 	        Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, (Object[])messageParameters);
+ 	        monitor.problem(problem);
+     	}
+     }
+    
+    /**
+     * Report a exception.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+     */
+     private void error(String message, Object model, Exception ex) {
+    	 if (monitor != null) {
+    		 Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, ex);
+    	     monitor.problem(problem);
+    	 }        
+     }
+
+
+    public Object read(QName attributeName, XMLStreamReader source) throws ContributionReadException, XMLStreamException {
+        
+        // Delegate to the processor associated with the attribute QName
+        int event = source.getEventType();
+        if (event == XMLStreamConstants.START_DOCUMENT) {
+            source.nextTag();
+        }
+
+        StAXAttributeProcessor<?> processor = null;
+        
+        //lookup for registered attribute processors
+        processor = (StAXAttributeProcessor<?>)processors.getProcessor(attributeName);
+        if (processor == null) {
+        	Location location = source.getLocation();
+            if (logger.isLoggable(Level.WARNING)) {                
+                logger.warning("Attribute " + attributeName + " cannot be processed. (" + location + ")");
+            }
+            warning("AttributeCannotBeProcessed", processors, attributeName, location);            
+        } else {
+        	return processor.read(attributeName, source);
+        }
+        
+        
+        //handle extension attributes without processors
+        processor = (StAXAttributeProcessor<?>)processors.getProcessor(UNKNOWN_ATTRIBUTE);
+        if (processor == null) {
+        	Location location = source.getLocation();
+            if (logger.isLoggable(Level.WARNING)) {                
+                logger.warning("Could not find Default Attribute processor !");
+            }
+            warning("DefaultAttributeProcessorNotAvailable", processors, UNKNOWN_ATTRIBUTE, location);            
+        }        	
+        
+        return processor == null ? null : processor.read(attributeName, source);
+    }
+    
+    @SuppressWarnings("unchecked")
+    public void write(Object model, XMLStreamWriter outputSource) throws ContributionWriteException, XMLStreamException {
+        
+    	if(model == null) {
+    		return;
+    	}
+    	
+        // Delegate to the processor associated with the model type
+    	StAXAttributeProcessor processor = processors.getProcessor(model.getClass());
+    	if(processor == null) {
+    		if (logger.isLoggable(Level.WARNING)) {
+    			logger.warning("No StAX processor is configured to handle " + model.getClass());
+    		}
+    		warning("NoStaxProcessor", processors, model.getClass());    		
+    	} else {
+    		processor.write(model, outputSource);
+    		return;
+    	}
+    	
+    	 //handle extension attributes without processors
+        processor = (StAXAttributeProcessor<?>)processors.getProcessor(UNKNOWN_ATTRIBUTE);
+        if(processor == null) {
+    		if (logger.isLoggable(Level.WARNING)) {
+    			logger.warning("No Default StAX processor is configured to handle " + model.getClass());
+    		}
+    		warning("NoDefaultStaxProcessor", processors, model.getClass());    		        	
+        } else {
+    		processor.write(model, outputSource);
+    		return;        	
+        }
+    }
+    
+    
+    
+    @SuppressWarnings("unchecked")
+    public void resolve(Object model, ModelResolver resolver) throws ContributionResolveException {
+
+        // Delegate to the processor associated with the model type
+        if (model != null) {
+        	StAXAttributeProcessor processor = processors.getProcessor(model.getClass());
+            if (processor != null) {
+                processor.resolve(model, resolver);
+            }
+        }
+    }
+    
+    /**
+     * Read a model from an InputStream.
+     * @param is The artifact InputStream
+     * @param type Model type
+     * @return The model
+     * @throws ContributionReadException
+     */
+    public <M> M read(InputStream is, Class<M> type) throws ContributionReadException {
+        return null;
+    }
+
+    /**
+     * Write a model to an OutputStream.
+     * @param model
+     * @param os
+     * @throws ContributionWriteException
+     */
+    public void write(Object model, OutputStream os) throws ContributionWriteException {
+        try {
+            XMLStreamWriter writer = outputFactory.createXMLStreamWriter(os);
+            write(model, writer);
+            writer.flush();
+            writer.close();
+        } catch (XMLStreamException e) {
+        	ContributionWriteException cw = new ContributionWriteException(e);
+        	error("ContributionWriteException", outputFactory, cw);
+            throw cw;
+        }
+    }
+
+    public QName getArtifactType() {
+        return null;
+    }
+    
+    public Class<Object> getModelType() {
+        return null;
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ExtensibleURLArtifactProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ExtensibleURLArtifactProcessor.java
new file mode 100644
index 0000000000..cc31d2e073
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ExtensibleURLArtifactProcessor.java
@@ -0,0 +1,139 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.net.URI;
+import java.net.URL;
+
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.monitor.Monitor;
+import org.apache.tuscany.sca.monitor.Problem;
+import org.apache.tuscany.sca.monitor.Problem.Severity;
+
+/**
+ * Implementation of an extensible URL artifact processor.
+ * 
+ * Takes a URLArtifactProcessorExtensionPoint and delegates to the proper URLArtifactProcessor
+ * by either fileName or fileExtention
+ * 
+ * @version $Rev$ $Date$
+ */
+public class ExtensibleURLArtifactProcessor
+    implements URLArtifactProcessor<Object> {
+    
+    private URLArtifactProcessorExtensionPoint processors;
+    private Monitor monitor;
+
+    /**
+     * Constructs a new ExtensibleURLArtifactProcessor.
+     * 
+     * @param processors
+     */
+    public ExtensibleURLArtifactProcessor(URLArtifactProcessorExtensionPoint processors, Monitor monitor) {
+        this.processors = processors;
+        this.monitor = monitor;
+    }
+    
+    /**
+     * Report a error.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+     */
+    private void error(String message, Object model, Object... messageParameters) {
+    	if (monitor != null) {
+	        Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, (Object[])messageParameters);
+	        monitor.problem(problem);
+    	}
+    }
+
+    @SuppressWarnings("unchecked")
+    public Object read(URL contributionURL, URI sourceURI, URL sourceURL) throws ContributionReadException {
+        URLArtifactProcessor<Object> processor = null;
+        
+        // Delegate to the processor associated with file extension
+        String fileName = getFileName(sourceURL);
+        
+        //try to retrieve a processor for the specific filename
+        processor = (URLArtifactProcessor<Object>)processors.getProcessor(fileName);
+        
+        if (processor == null) {
+            //try to find my file type (extension)
+            String extension = sourceURL.getPath();
+            
+            int extensionStart = extension.lastIndexOf('.');
+            //handle files without extension (e.g NOTICE)
+            if (extensionStart > 0) {
+                extension = extension.substring(extensionStart);
+                processor = (URLArtifactProcessor<Object>)processors.getProcessor(extension);            
+            }
+        }
+        
+        if (processor == null) {
+            return null;
+        }
+        return processor.read(contributionURL, sourceURI, sourceURL);
+    }
+
+    @SuppressWarnings("unchecked")
+    public void resolve(Object model, ModelResolver resolver) throws ContributionResolveException {
+
+        // Delegate to the processor associated with the model type
+        if (model != null) {
+            URLArtifactProcessor processor = processors.getProcessor(model.getClass());
+            if (processor != null) {
+                processor.resolve(model, resolver);
+            }
+        }
+    }
+    
+    public <M> M read(URL contributionURL, URI artifactURI, URL artifactUrl, Class<M> type) 
+        throws ContributionReadException {
+        Object mo = read(contributionURL, artifactURI, artifactUrl);
+        if (type.isInstance(mo)) {
+            return type.cast(mo);
+        } else {
+            UnrecognizedElementException e = new UnrecognizedElementException(null);
+            e.setResourceURI(artifactURI.toString());
+            error("UnrecognizedElementException", processors, artifactURI.toString());
+            throw e;
+        }
+    }
+    
+    public String getArtifactType() {
+        return null;
+    }
+    
+    public Class<Object> getModelType() {
+        return null;
+    }
+
+    /**
+     * Returns the file name from a URL.
+     * @param url
+     * @return
+     */
+    private static String getFileName(URL url){
+        String fileName = url.getPath();
+        int pos = fileName.lastIndexOf("/");
+        
+        return fileName.substring(pos +1);
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXArtifactProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXArtifactProcessor.java
new file mode 100644
index 0000000000..1bf9b4d494
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXArtifactProcessor.java
@@ -0,0 +1,59 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import javax.xml.namespace.QName;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamReader;
+import javax.xml.stream.XMLStreamWriter;
+
+
+/**
+ * An artifact processor that can read models from a StAX XMLStreamReader.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface StAXArtifactProcessor<M> extends ArtifactProcessor<M> {
+
+    /**
+     * Reads a model from an XMLStreamReader.
+     * 
+     * @param reader The XMLStreamReader
+     * @return A model representation of the input.
+     */
+    M read(XMLStreamReader reader) throws ContributionReadException, XMLStreamException;
+    
+    /**
+     * Writes a model to an XMLStreamWriter.
+     * 
+     * @param model A model representing the source
+     * @param writer The XML stream writer
+     * @throws ContributionWriteException
+     * @throws XMLStreamException
+     */
+    void write(M model, XMLStreamWriter writer) throws ContributionWriteException, XMLStreamException;
+    
+    /**
+     * Returns the type of artifact handled by this artifact processor.
+     *  
+     * @return The type of artifact handled by this artifact processor
+     */
+    QName getArtifactType();
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXArtifactProcessorExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXArtifactProcessorExtensionPoint.java
new file mode 100644
index 0000000000..9700e2bc60
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXArtifactProcessorExtensionPoint.java
@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+/**
+ * An extension point for StAX artifact processors.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface StAXArtifactProcessorExtensionPoint extends 
+    ArtifactProcessorExtensionPoint<StAXArtifactProcessor> {
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXAttributeProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXAttributeProcessor.java
new file mode 100644
index 0000000000..b25bf0d669
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXAttributeProcessor.java
@@ -0,0 +1,61 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import javax.xml.namespace.QName;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamReader;
+import javax.xml.stream.XMLStreamWriter;
+
+
+
+/**
+ * An artifact processor that can read attributes from a StAX XMLStreamReader.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface StAXAttributeProcessor<M> extends ArtifactProcessor<M>{
+
+    /**
+     * Reads a model from an XMLStreamReader.
+     * 
+     * @param reader The XMLStreamReader
+     * @return A model representation of the input.
+     */
+    M read(QName attributeName, XMLStreamReader reader) throws ContributionReadException, XMLStreamException;
+    
+    /**
+     * Writes a model to an XMLStreamWriter.
+     * 
+     * @param model A model representing the source
+     * @param writer The XML stream writer
+     * @throws ContributionWriteException
+     * @throws XMLStreamException
+     */
+    void write(M model, XMLStreamWriter writer) throws ContributionWriteException, XMLStreamException;
+    
+    /**
+     * Returns the type of artifact handled by this artifact processor.
+     *  
+     * @return The type of artifact handled by this artifact processor
+     */
+    QName getArtifactType();
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXAttributeProcessorExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXAttributeProcessorExtensionPoint.java
new file mode 100644
index 0000000000..ebad243c1c
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/StAXAttributeProcessorExtensionPoint.java
@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+/**
+ * An extension point for StAX artifact processors.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface StAXAttributeProcessorExtensionPoint extends 
+    ArtifactProcessorExtensionPoint<StAXAttributeProcessor> {
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/URLArtifactProcessor.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/URLArtifactProcessor.java
new file mode 100644
index 0000000000..c44ca0c66a
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/URLArtifactProcessor.java
@@ -0,0 +1,50 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.net.URI;
+import java.net.URL;
+
+
+/**
+ * An artifact processor that can read models from a URL.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface URLArtifactProcessor<M> extends ArtifactProcessor<M> {
+
+    /**
+     * Reads a model from a URL.
+     * 
+     * @param contributionURL Contribution location URL
+     * @param artifactURI Artifact URI
+     * @param artifactURL Artifact location URL 
+     * @return A model representation of the input.
+     */
+    M read(URL contributionURL, URI artifactURI, URL artifactURL) throws ContributionReadException;
+    
+    /**
+     * Returns the type of artifact handled by this artifact processor.
+     *  
+     * @return The type of artifact handled by this artifact processor
+     */
+    String getArtifactType();
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/URLArtifactProcessorExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/URLArtifactProcessorExtensionPoint.java
new file mode 100644
index 0000000000..7714586951
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/URLArtifactProcessorExtensionPoint.java
@@ -0,0 +1,29 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+/**
+ * An extension point for URL artifact processors.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface URLArtifactProcessorExtensionPoint extends
+    ArtifactProcessorExtensionPoint<URLArtifactProcessor> {
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/UnrecognizedElementException.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/UnrecognizedElementException.java
new file mode 100644
index 0000000000..4c6f0b7282
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/UnrecognizedElementException.java
@@ -0,0 +1,48 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+import javax.xml.namespace.QName;
+
+/**
+ * Exception that indicates an element was encountered that could not be handled.
+ *
+ * @version $Rev$ $Date$
+ */
+public class UnrecognizedElementException extends ContributionReadException {
+    private static final long serialVersionUID = 2549543622209829032L;
+    private final QName element;
+
+    /**
+     * Constructor that indicates which element could not be handled.
+     * @param element the element that could not be handled
+     */
+    public UnrecognizedElementException(QName element) {
+        super("Unrecognized element: " + element);
+        this.element = element;
+    }
+
+    /**
+     * Returns the element that could not be handled.
+     * @return the element that could not be handled.
+     */
+    public QName getElement() {
+        return element;
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/UnsupportedContentTypeException.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/UnsupportedContentTypeException.java
new file mode 100644
index 0000000000..8a166e42f0
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/UnsupportedContentTypeException.java
@@ -0,0 +1,43 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+
+/**
+ * Exception thrown to indicate that a Content-Type is not supported by this SCA Domain.
+ * The Content-Type value supplied will be returned as the message text for this exception.
+ * 
+ * FIXME Don't use as it's deprecated and replaced by UnsupportedPackageTypeException.
+ *
+ * @version $Rev$ $Date$
+ */
+@Deprecated
+public class UnsupportedContentTypeException extends ContributionException {
+    private static final long serialVersionUID = -1831797280021355672L;
+
+    /**
+     * Constructs a new UnsupportedContentTypeException.
+     *
+     * @param message
+     */
+    public UnsupportedContentTypeException(String message) {
+        super(message);
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/UnsupportedPackageTypeException.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/UnsupportedPackageTypeException.java
new file mode 100644
index 0000000000..ce94cef6a0
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/UnsupportedPackageTypeException.java
@@ -0,0 +1,40 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.processor;
+
+
+/**
+ * Exception thrown to indicate that a Content-Type is not supported by this SCA Domain.
+ * The Content-Type value supplied will be returned as the message text for this exception.
+ *
+ * @version $Rev$ $Date$
+ */
+public class UnsupportedPackageTypeException extends ContributionException {
+    private static final long serialVersionUID = -1831797280021355672L;
+
+    /**
+     * Constructs a new UnsupportedPackageTypeException.
+     *
+     * @param message
+     */
+    public UnsupportedPackageTypeException(String message) {
+        super(message);
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ValidatingXMLInputFactory.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ValidatingXMLInputFactory.java
new file mode 100644
index 0000000000..c0eef5a7a8
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ValidatingXMLInputFactory.java
@@ -0,0 +1,30 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import javax.xml.stream.XMLInputFactory;
+
+/**
+ * Base marker class for validating XML input factories.
+ *
+ * @version $Rev$ $Date$
+ */
+public abstract class ValidatingXMLInputFactory extends XMLInputFactory {
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ValidatingXMLStreamReader.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ValidatingXMLStreamReader.java
new file mode 100644
index 0000000000..ee8fbba5a5
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ValidatingXMLStreamReader.java
@@ -0,0 +1,387 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.util.logging.Logger;
+
+import javax.xml.namespace.QName;
+import javax.xml.stream.Location;
+import javax.xml.stream.XMLStreamConstants;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.XMLStreamReader;
+import javax.xml.stream.util.StreamReaderDelegate;
+import javax.xml.validation.Schema;
+import javax.xml.validation.ValidatorHandler;
+
+import org.apache.tuscany.sca.monitor.Monitor;
+import org.apache.tuscany.sca.monitor.Problem;
+import org.apache.tuscany.sca.monitor.Problem.Severity;
+import org.xml.sax.Attributes;
+import org.xml.sax.ErrorHandler;
+import org.xml.sax.Locator;
+import org.xml.sax.SAXException;
+import org.xml.sax.SAXParseException;
+import org.xml.sax.helpers.AttributesImpl;
+
+/**
+ * 
+ * A validating XMLStreamReader that reports XMLSchema validation errors.
+ *
+ * @version $Rev$ $Date$
+ */
+class ValidatingXMLStreamReader extends StreamReaderDelegate implements XMLStreamReader {
+    private static final Logger logger = Logger.getLogger(ValidatingXMLStreamReader.class.getName());
+    
+    private int level;
+    private ValidatorHandler handler;
+    private final Monitor monitor;
+    
+    /**
+     * Constructs a new ValidatingXMLStreamReader.
+     * 
+     * @param reader
+     * @param schema
+     * @throws XMLStreamException
+     */
+    ValidatingXMLStreamReader(XMLStreamReader reader, Schema schema, Monitor monitor) throws XMLStreamException {
+        super(reader);
+        this.monitor = monitor;
+        if (schema == null) {
+            return;
+        }
+        
+        handler = schema.newValidatorHandler();
+        handler.setDocumentLocator(new LocatorAdapter());
+        try {
+            handler.setFeature("http://xml.org/sax/features/namespace-prefixes", true);
+        } catch (SAXException e) {
+        	XMLStreamException xse = new XMLStreamException(e);
+        	error("XMLStreamException", handler, xse);
+            throw xse;
+        }
+        
+        // These validation errors are just warnings for us as we want to support
+        // running from an XML document with XSD validation errors, as long as we can
+        // get the metadata we need from the document
+        handler.setErrorHandler(new ErrorHandler() {        	
+            private String getMessage(SAXParseException e) {
+                return "XMLSchema validation problem in: " + e.getSystemId() + ", line: " + e.getLineNumber() + ", column: " + e.getColumnNumber() + "\n" + e.getMessage();
+            }
+            
+            public void error(SAXParseException exception) throws SAXException {            	
+            	if (ValidatingXMLStreamReader.this.monitor == null)
+            		logger.warning(getMessage(exception));
+            	else            		
+            		ValidatingXMLStreamReader.this.error("SchemaError", ValidatingXMLStreamReader.this.getClass(), exception.getSystemId(), 
+                   		exception.getLineNumber(), exception.getColumnNumber(), exception.getMessage());                              
+            }
+            
+            public void fatalError(SAXParseException exception) throws SAXException {            	
+            	if (ValidatingXMLStreamReader.this.monitor == null)
+            		logger.warning(getMessage(exception));
+            	else
+            		ValidatingXMLStreamReader.this.error("SchemaFatalError", ValidatingXMLStreamReader.this.getClass(), exception.getSystemId(), 
+                       	exception.getLineNumber(), exception.getColumnNumber(), exception.getMessage());               
+            }
+            
+            public void warning(SAXParseException exception) throws SAXException {
+            	if (ValidatingXMLStreamReader.this.monitor == null)
+            		logger.warning(getMessage(exception));
+            	else
+            		ValidatingXMLStreamReader.this.warning("SchemaWarning", ValidatingXMLStreamReader.this.getClass(), exception.getSystemId(), 
+                       	exception.getLineNumber(), exception.getColumnNumber(), exception.getMessage());                
+            }
+        });
+    }
+    
+    /**
+     * Report a warning.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+     */
+    private void warning(String message, Object model, Object... messageParameters) {
+        if (monitor != null) {
+            Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.WARNING, model, message, (Object[])messageParameters);
+            monitor.problem(problem);
+    	}
+    }
+    
+    /**
+     * Report a error.
+     * 
+     * @param problems
+     * @param message
+     * @param model
+     */
+    private void error(String message, Object model, Object... messageParameters) {
+        if (monitor != null) {
+            Problem problem = monitor.createProblem(this.getClass().getName(), "contribution-validation-messages", Severity.ERROR, model, message, (Object[])messageParameters);
+            monitor.problem(problem);
+        }
+    }
+
+    @Override
+    public int next() throws XMLStreamException {
+        if (handler == null) {
+            return super.next();
+        }
+
+        int event = super.next();
+        try {
+            switch (event) {
+                case XMLStreamConstants.START_DOCUMENT:
+                    level++;
+                    handler.startDocument();
+                    break;
+                case XMLStreamConstants.START_ELEMENT:
+                    level++;
+                    handleStartElement();
+                    break;
+                case XMLStreamConstants.PROCESSING_INSTRUCTION:
+                    handler.processingInstruction(super.getPITarget(), super.getPIData());
+                    break;
+                case XMLStreamConstants.CHARACTERS:
+                case XMLStreamConstants.CDATA:
+                case XMLStreamConstants.SPACE:
+                case XMLStreamConstants.ENTITY_REFERENCE:
+                    handler.characters(super.getTextCharacters(), super.getTextStart(), super.getTextLength());
+                    break;
+                case XMLStreamConstants.END_ELEMENT:
+                    handleEndElement();
+                    level--;
+                    break;
+                case XMLStreamConstants.END_DOCUMENT:
+                    handler.endDocument();
+                    break;
+            }
+        } catch (SAXException e) {
+        	XMLStreamException xse = new XMLStreamException(e.getMessage(), e);
+        	error("XMLStreamException", handler, xse);
+            throw xse;
+        }
+        return event;
+    }
+    
+    @Override
+    public int nextTag() throws XMLStreamException {
+        if (handler == null) {
+            return super.nextTag();
+        }
+        
+        for (;;) {
+            int event = super.getEventType();
+            try {
+                switch (event) {
+                    case XMLStreamConstants.START_DOCUMENT:
+                        level++;
+                        handler.startDocument();
+                        break;
+                    case XMLStreamConstants.START_ELEMENT:
+                        level++;
+                        handleStartElement();
+                        return event;
+                    case XMLStreamConstants.PROCESSING_INSTRUCTION:
+                        handler.processingInstruction(super.getPITarget(), super.getPIData());
+                        break;
+                    case XMLStreamConstants.CHARACTERS:
+                    case XMLStreamConstants.CDATA:
+                    case XMLStreamConstants.SPACE:
+                    case XMLStreamConstants.ENTITY_REFERENCE:
+                        handler.characters(super.getTextCharacters(), super.getTextStart(), super.getTextLength());
+                        break;
+                    case XMLStreamConstants.END_ELEMENT:
+                        handleEndElement();
+                        level--;
+                        return event;
+                    case XMLStreamConstants.END_DOCUMENT:
+                        handler.endDocument();
+                        return event;
+                }
+            } catch (SAXException e) {
+            	XMLStreamException xse = new XMLStreamException(e);
+            	error("XMLStreamException", handler, xse);
+                throw xse;
+            }
+            super.next();
+        }
+    }
+    
+    @Override
+    public String getElementText() throws XMLStreamException {
+        if (handler == null) {
+            return super.getElementText();
+        }
+
+        if (getEventType() != XMLStreamConstants.START_ELEMENT) {
+            return super.getElementText();
+        }
+        StringBuffer text = new StringBuffer();
+
+        for (;;) {
+            int event = next();
+            switch (event) {
+                case XMLStreamConstants.END_ELEMENT:
+                    return text.toString();
+                    
+                case XMLStreamConstants.COMMENT:
+                case XMLStreamConstants.PROCESSING_INSTRUCTION:
+                    continue;
+                    
+                case CHARACTERS:
+                case CDATA:
+                case SPACE:
+                case ENTITY_REFERENCE:
+                    text.append(getText());
+                    break;
+                    
+                default:
+                    break;
+            }
+        }
+    }
+    
+    /**
+     * Handle a start element event.
+     * 
+     * @throws SAXException
+     */
+    private void handleStartElement() throws SAXException {
+
+        // send startPrefixMapping events immediately before startElement event
+        int nsCount = super.getNamespaceCount();
+        for (int i = 0; i < nsCount; i++) {
+            String prefix = super.getNamespacePrefix(i);
+            if (prefix == null) { // true for default namespace
+                prefix = "";
+            }
+            handler.startPrefixMapping(prefix, super.getNamespaceURI(i));
+        }
+
+        // fire startElement
+        QName qname = super.getName();
+        String prefix = qname.getPrefix();
+        String rawname;
+        if (prefix == null || prefix.length() == 0) {
+            rawname = qname.getLocalPart();
+        } else {
+            rawname = prefix + ':' + qname.getLocalPart();
+        }
+        Attributes attrs = getAttributes();
+        handler.startElement(qname.getNamespaceURI(), qname.getLocalPart(), rawname, attrs);
+    }
+
+    /**
+     * Handle an endElement event.
+     * 
+     * @throws SAXException
+     */
+    private void handleEndElement() throws SAXException {
+
+        // fire endElement
+        QName qname = super.getName();
+        handler.endElement(qname.getNamespaceURI(), qname.getLocalPart(), qname.toString());
+
+        // send endPrefixMapping events immediately after endElement event
+        // we send them in the opposite order to that returned but this is not
+        // actually required by SAX
+        int nsCount = super.getNamespaceCount();
+        for (int i = nsCount - 1; i >= 0; i--) {
+            String prefix = super.getNamespacePrefix(i);
+            if (prefix == null) { // true for default namespace
+                prefix = "";
+            }
+            handler.endPrefixMapping(prefix);
+        }
+    }
+
+    /**
+     * Get the attributes associated with the current START_ELEMENT event.
+     * 
+     * @return the StAX attributes converted to org.xml.sax.Attributes
+     */
+    private Attributes getAttributes() {
+        AttributesImpl attrs = new AttributesImpl();
+
+        // add namespace declarations
+        for (int i = 0; i < super.getNamespaceCount(); i++) {
+            String prefix = super.getNamespacePrefix(i);
+            String uri = super.getNamespaceURI(i);
+            if (prefix == null) {
+                attrs.addAttribute("", "", "xmlns", "CDATA", uri);
+            } else {
+                attrs.addAttribute("", "", "xmlns:" + prefix, "CDATA", uri);
+            }
+        }
+
+        // Regular attributes
+        for (int i = 0; i < super.getAttributeCount(); i++) {
+            String uri = super.getAttributeNamespace(i);
+            if (uri == null) {
+                uri = "";
+            }
+            String localName = super.getAttributeLocalName(i);
+            String prefix = super.getAttributePrefix(i);
+            String qname;
+            if (prefix == null || prefix.length() == 0) {
+                qname = localName;
+            } else {
+                qname = prefix + ':' + localName;
+            }
+            String type = super.getAttributeType(i);
+            String value = super.getAttributeValue(i);
+
+            attrs.addAttribute(uri, localName, qname, type, value);
+        }
+
+        return attrs;
+    }
+
+    /**
+     * Adapter for mapping Locator information.
+     */
+    private final class LocatorAdapter implements Locator {
+
+        private LocatorAdapter() {
+        }
+
+        public int getColumnNumber() {
+            Location location = getLocation();
+            return location == null ? 0 : location.getColumnNumber();
+        }
+
+        public int getLineNumber() {
+            Location location = getLocation();
+            return location == null ? 0 : location.getLineNumber();
+        }
+
+        public String getPublicId() {
+            Location location = getLocation();
+            return location == null ? "" : location.getPublicId();
+        }
+
+        public String getSystemId() {
+            Location location = getLocation();
+            return location == null ? "" : location.getSystemId();
+        }
+    }
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ValidationSchemaExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ValidationSchemaExtensionPoint.java
new file mode 100644
index 0000000000..cc3bb59a5b
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/processor/ValidationSchemaExtensionPoint.java
@@ -0,0 +1,52 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import java.util.List;
+
+
+/**
+ * An extension point for XML schemas used for validation.
+ *
+ * @version $Rev$ $Date$
+ */
+public interface ValidationSchemaExtensionPoint {
+    
+    /**
+     * Add a schema.
+     * 
+     * @param uri the URI of the schema
+     */
+    void addSchema(String uri);
+    
+    /**
+     * Remove a schema.
+     * 
+     * @param uri the URI of the schema
+     */
+    void removeSchema(String uri);
+    
+    /**
+     * Returns the list of schemas registered in the extension point.
+     * @return the list of schemas
+     */
+    List<String> getSchemas();
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ClassReference.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ClassReference.java
new file mode 100644
index 0000000000..f3555ee71e
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ClassReference.java
@@ -0,0 +1,107 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+import java.lang.ref.WeakReference;
+
+import org.apache.tuscany.sca.assembly.Base;
+
+/**
+ * A weak reference to a class, which should be used to register classes
+ * with an ArtifactResolver and resolve these classes later.
+ * 
+ * FIXME The core contribution model should not have dependencies on classes
+ * and ClassLoaders. This should move to the Java import support module.
+ *
+ * @version $Rev$ $Date$
+ */
+public class ClassReference implements Base {
+    
+    private WeakReference<Class<?>> clazz;
+    private String className;
+
+    /**
+     * Constructs a new ClassReference.
+     * 
+     * @param clazz The class reference
+     */
+    public ClassReference(Class<?> clazz) {
+        this.clazz = new WeakReference<Class<?>>(clazz);
+        this.className = clazz.getName();
+    }
+    
+    /**
+     * Constructs a new ClassReference.
+     * 
+     * @param className The class name
+     */
+    public ClassReference(String className) {
+        this.className = className;
+    }
+    
+    /**
+     * Get the referenced class.
+     * 
+     * @return The referenced class
+     */
+    public Class<?> getJavaClass() {
+        if (clazz != null) {
+            return clazz.get();
+        } else {
+            return null;
+        }
+    }
+    
+    /**
+     * Get the referenced class name.
+     * 
+     * @return The class name
+     */
+    public String getClassName() {
+        return className;
+    }
+    
+    public boolean isUnresolved() {
+        return clazz == null;
+    }
+    
+    public void setUnresolved(boolean unresolved) {
+        throw new IllegalStateException();
+    }
+
+    @Override
+    public int hashCode() {
+        return className.hashCode();
+    }
+    
+    @Override
+    public boolean equals(Object obj) {
+        if (obj == this) {
+            return true;
+        } else {
+            if (obj instanceof ClassReference) {
+                return className.equals(((ClassReference)obj).className);
+            } else {
+                return false;
+            }
+        }
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultDelegatingModelResolver.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultDelegatingModelResolver.java
new file mode 100644
index 0000000000..13c622adf0
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultDelegatingModelResolver.java
@@ -0,0 +1,68 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+import java.util.List;
+
+import org.apache.tuscany.sca.assembly.Base;
+
+/**
+ * A model resolver implementation that delegates to a list of model resolvers.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultDelegatingModelResolver implements ModelResolver {
+    
+    private List<ModelResolver> resolvers;
+    
+    public DefaultDelegatingModelResolver(List<ModelResolver> resolvers) {
+        this.resolvers = resolvers;
+    }
+
+    public void addModel(Object resolved) {
+        throw new IllegalStateException();
+    }
+
+    public Object removeModel(Object resolved) {
+        throw new IllegalStateException();
+    }
+
+    public <T> T resolveModel(Class<T> modelClass, T unresolved) {
+        
+        //TODO optimize and cache results of the resolution later
+        
+        // Go over all resolvers
+        for (ModelResolver resolver: resolvers) {
+            
+            Object resolved = resolver.resolveModel(modelClass, unresolved);
+            
+            // Return the resolved model object
+            if (resolved instanceof Base) {
+                if (!((Base)resolved).isUnresolved()) {
+                    return modelClass.cast(resolved);
+                }
+            }
+        }
+
+        // Model object was not resolved
+        return unresolved;
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultImportAllModelResolver.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultImportAllModelResolver.java
new file mode 100644
index 0000000000..c6facd2b02
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultImportAllModelResolver.java
@@ -0,0 +1,80 @@
+/*

+ * Licensed to the Apache Software Foundation (ASF) under one

+ * or more contributor license agreements.  See the NOTICE file

+ * distributed with this work for additional information

+ * regarding copyright ownership.  The ASF licenses this file

+ * to you under the Apache License, Version 2.0 (the

+ * "License"); you may not use this file except in compliance

+ * with the License.  You may obtain a copy of the License at

+ * 

+ *   http://www.apache.org/licenses/LICENSE-2.0

+ * 

+ * Unless required by applicable law or agreed to in writing,

+ * software distributed under the License is distributed on an

+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+ * KIND, either express or implied.  See the License for the

+ * specific language governing permissions and limitations

+ * under the License.    

+ */

+

+package org.apache.tuscany.sca.contribution.resolver;

+

+import java.util.List;

+

+import org.apache.tuscany.sca.assembly.Base;

+import org.apache.tuscany.sca.contribution.Contribution;

+import org.apache.tuscany.sca.contribution.Export;

+import org.apache.tuscany.sca.contribution.Import;

+

+/**

+ * A model resolver implementation that considers Exports in a list of contributions.

+ *

+ * @version $Rev: 560435 $ $Date: 2007-07-27 18:26:55 -0700 (Fri, 27 Jul 2007) $

+ */

+public class DefaultImportAllModelResolver implements ModelResolver {

+    

+    private Import import_;

+    private List<Contribution> contributions;

+    

+    public DefaultImportAllModelResolver(Import import_, List<Contribution> contributions) {

+        this.import_ = import_;

+        this.contributions = contributions;

+    }

+

+    public void addModel(Object resolved) {

+        throw new IllegalStateException();

+    }

+

+    public Object removeModel(Object resolved) {

+        throw new IllegalStateException();

+    }

+

+    public <T> T resolveModel(Class<T> modelClass, T unresolved) {

+        

+        //TODO optimize and cache results of the resolution later

+        

+        // Go over all available contributions

+        for (Contribution contribution : contributions) {

+            

+            // Go over all exports in the contribution

+            for (Export export : contribution.getExports()) {

+                

+                    // If the export matches the export, try to resolve the model object

+                    if (import_.match(export)) {

+                        Object resolved = export.getModelResolver().resolveModel(modelClass, unresolved);

+                        

+                        // Return the resolved model object

+                        if (resolved instanceof Base) {

+                            if (!((Base)resolved).isUnresolved()) {

+                                return modelClass.cast(resolved);

+                            }

+                        }

+                    }

+            }

+        }

+

+        // Model object was not resolved

+        return unresolved;

+    }

+

+}

diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultImportModelResolver.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultImportModelResolver.java
new file mode 100644
index 0000000000..9ae57c41d0
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultImportModelResolver.java
@@ -0,0 +1,69 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+import java.util.List;
+
+import org.apache.tuscany.sca.assembly.Base;
+import org.apache.tuscany.sca.contribution.Export;
+
+/**
+ * A model resolver implementation that delegates to a list of exports.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultImportModelResolver implements ModelResolver {
+    
+    private List<Export> exports;
+    
+    public DefaultImportModelResolver(List<Export> exports) {
+        this.exports = exports;
+    }
+
+    public void addModel(Object resolved) {
+        throw new IllegalStateException();
+    }
+
+    public Object removeModel(Object resolved) {
+        throw new IllegalStateException();
+    }
+
+    public <T> T resolveModel(Class<T> modelClass, T unresolved) {
+        
+        //TODO optimize and cache results of the resolution later
+        
+        // Go over all exports
+        for (Export export: exports) {
+            
+            Object resolved = export.getModelResolver().resolveModel(modelClass, unresolved);
+            
+            // Return the resolved model object
+            if (resolved instanceof Base) {
+                if (!((Base)resolved).isUnresolved()) {
+                    return modelClass.cast(resolved);
+                }
+            }
+        }
+
+        // Model object was not resolved
+        return unresolved;
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultModelResolver.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultModelResolver.java
new file mode 100644
index 0000000000..bf175813f3
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultModelResolver.java
@@ -0,0 +1,66 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+import java.util.HashMap;
+import java.util.Map;
+
+
+/**
+ * A default implementation of a model resolver based on a map.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultModelResolver implements ModelResolver {
+    
+    private Map<Object, Object> map = new HashMap<Object, Object>();
+    
+    public DefaultModelResolver() {
+    }
+    
+    public <T> T resolveModel(Class<T> modelClass, T unresolved) {
+        Object resolved = map.get(unresolved);
+        if (resolved != null) {
+            
+            // Return the resolved object
+            return modelClass.cast(resolved);
+            
+        } else {
+            
+            // Return the unresolved object
+            return unresolved;
+        }
+    }
+    
+    public void addModel(Object resolved) {
+        map.put(resolved, resolved);
+    }
+    
+    public Object removeModel(Object resolved) {
+        return map.remove(resolved);
+    }
+    
+    // FIXME: TUSCANY-2499: temporarily  give access to the models to get the jms binding
+    //  use of definitions.xml working while the definitions.xml processing is being refactored
+    public Map getModels() {
+        return map;
+    }
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultModelResolverExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultModelResolverExtensionPoint.java
new file mode 100644
index 0000000000..878a2efdab
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/DefaultModelResolverExtensionPoint.java
@@ -0,0 +1,114 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.resolver;
+
+import java.io.IOException;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+
+
+/**
+ * The default implementation of a model resolver extension point.
+ * 
+ * @version $Rev$ $Date$
+ */
+public class DefaultModelResolverExtensionPoint implements ModelResolverExtensionPoint {
+    
+    private final Map<Class<?>, Class<? extends ModelResolver>> resolvers = new HashMap<Class<?>, Class<? extends ModelResolver>>();
+    private Map<String, ServiceDeclaration> loadedResolvers;
+
+    /**
+     * Constructs a new DefaultModelResolverExtensionPoint.
+     */
+    public DefaultModelResolverExtensionPoint() {
+    }
+
+    public void addResolver(Class<?> modelType, Class<? extends ModelResolver> resolver) {
+        resolvers.put(modelType, resolver);
+    }
+
+    public void removeResolver(Class<?> modelType) {
+        resolvers.remove(modelType);
+    }
+
+    @SuppressWarnings("unchecked")
+    public Class<? extends ModelResolver> getResolver(Class<?> modelType) {
+        loadModelResolvers();
+        
+        Class<?>[] classes = modelType.getInterfaces();
+        for (Class<?> c : classes) {
+            Class<? extends ModelResolver> resolver = resolvers.get(c);
+            if (resolver == null) {
+                ServiceDeclaration resolverClass = loadedResolvers.get(c.getName());
+                if (resolverClass != null) {
+                    try {
+                        return (Class<? extends ModelResolver>)resolverClass.loadClass();
+                    } catch (ClassNotFoundException e) {
+                        throw new IllegalArgumentException(e);
+                    }
+                }
+            } else {
+                return resolver;
+            }
+        }
+
+        Class<? extends ModelResolver > resolver = resolvers.get(modelType);
+        if (resolver == null) {
+            ServiceDeclaration resolverClass = loadedResolvers.get(modelType.getName());
+            if (resolverClass != null) {
+                try {
+                    return (Class<? extends ModelResolver>)resolverClass.loadClass();
+                } catch (ClassNotFoundException e) {
+                    throw new IllegalArgumentException(e);
+                }
+            }
+        }
+        return resolver;
+    }
+
+    /**
+     * Dynamically load model resolvers declared under META-INF/services
+     */
+    private void loadModelResolvers() {
+        if (loadedResolvers != null)
+            return;
+        loadedResolvers = new HashMap<String, ServiceDeclaration>();
+
+        // Get the model resolver service declarations
+        Set<ServiceDeclaration> modelResolverDeclarations; 
+        try {
+            modelResolverDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations(ModelResolver.class.getName());
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
+        
+        // Load model resolvers
+        for (ServiceDeclaration modelResolverDeclaration: modelResolverDeclarations) {
+            Map<String, String> attributes = modelResolverDeclaration.getAttributes();
+            String model = attributes.get("model");
+
+            loadedResolvers.put(model, modelResolverDeclaration);
+        }
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ExtensibleModelResolver.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ExtensibleModelResolver.java
new file mode 100644
index 0000000000..b48742bcae
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ExtensibleModelResolver.java
@@ -0,0 +1,200 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+import java.lang.reflect.Constructor;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.tuscany.sca.contribution.Contribution;
+import org.apache.tuscany.sca.core.FactoryExtensionPoint;
+
+/**
+ * An implementation of an extensible model resolver which delegates to the
+ * proper resolver extension based on the class of the model to resolve.
+ * 
+ * @version $Rev$ $Date$
+ */
+public class ExtensibleModelResolver implements ModelResolver {
+    private final ModelResolverExtensionPoint resolverExtensions;
+    private final FactoryExtensionPoint modelFactories;
+    private final Contribution contribution;
+    private ModelResolver defaultResolver;
+    private final Map<Class<?>, ModelResolver> resolversByModelType = new HashMap<Class<?>, ModelResolver>();
+    private final Map<Class<?>, ModelResolver> resolversByImplementationClass = new HashMap<Class<?>, ModelResolver>();
+    private Map<Object, Object> map = new HashMap<Object, Object>();
+    private Object lastUnresolved;
+
+    /**
+     * Constructs an extensible model resolver
+     * 
+     * @param contribution
+     * @param resolverExtensions
+     * @param modelFactories
+     * @param defaultResolver
+     */
+    @Deprecated
+    public ExtensibleModelResolver(Contribution contribution,
+                                   ModelResolverExtensionPoint resolverExtensions,
+                                   FactoryExtensionPoint modelFactories,
+                                   ModelResolver defaultResolver) {
+        this.contribution = contribution;
+        this.resolverExtensions = resolverExtensions;
+        this.modelFactories = modelFactories;
+        //FIXME Remove this default resolver, this is currently used to resolve policy declarations
+        // but they should be handled by the contribution import/export mechanism instead of this
+        // defaultResolver hack.
+        this.defaultResolver = defaultResolver;
+    }
+
+    /**
+     * Constructs an extensible model resolver
+     * 
+     * @param resolverExtensions
+     * @param contribution
+     * @param modelFactories
+     */
+    public ExtensibleModelResolver(Contribution contribution,
+                                   ModelResolverExtensionPoint resolverExtensions,
+                                   FactoryExtensionPoint modelFactories) {
+        this.contribution = contribution;
+        this.resolverExtensions = resolverExtensions;
+        this.modelFactories = modelFactories;
+    }
+
+    /**
+     * Returns the proper resolver instance based on the interfaces of the model
+     * If one is not available on the registry, instantiate on demand
+     * 
+     * @param modelType
+     * @return
+     */
+    private ModelResolver getModelResolverInstance(Class<?> modelType) {
+        // Look up a model resolver instance for the model class or
+        // each implemented interface
+        Class<?>[] interfaces = modelType.getInterfaces();
+        Class<?>[] classes = new Class<?>[interfaces.length + 1];
+        classes[0] = modelType;
+        if (interfaces.length != 0) {
+            System.arraycopy(interfaces, 0, classes, 1, interfaces.length);
+        }
+        for (Class<?> c : classes) {
+
+            // Look up an existing model resolver instance
+            ModelResolver resolverInstance = resolversByModelType.get(c);
+            if (resolverInstance != null) {
+                return resolverInstance;
+            }
+
+            // We don't have an instance, lookup a model resolver class
+            // and instantiate it
+            Class<? extends ModelResolver> resolverClass = resolverExtensions.getResolver(c);
+            if (resolverClass != null) {
+
+                // Construct the model resolver instance and cache it
+                resolverInstance = resolversByImplementationClass.get(resolverClass);
+                if (resolverInstance != null) {
+                    resolversByModelType.put(c, resolverInstance);
+                    return resolverInstance;
+                }
+                try {
+                    Constructor<? extends ModelResolver> constructor =
+                        resolverClass
+                            .getConstructor(new Class[] {Contribution.class, FactoryExtensionPoint.class});
+                    if (constructor != null) {
+
+                        resolverInstance = constructor.newInstance(contribution, modelFactories);
+                        resolversByImplementationClass.put(resolverClass, resolverInstance);
+                        resolversByModelType.put(c, resolverInstance);
+                        return resolverInstance;
+                    }
+                } catch (Exception e) {
+                    throw new IllegalStateException(e);
+                }
+            }
+        }
+
+        return null;
+    }
+
+    public void addModel(Object resolved) {
+        ModelResolver resolver = getModelResolverInstance(resolved.getClass());
+        if (resolver != null) {
+            resolver.addModel(resolved);
+        } else {
+            map.put(resolved, resolved);
+        }
+    }
+
+    public Object removeModel(Object resolved) {
+        ModelResolver resolver = getModelResolverInstance(resolved.getClass());
+        if (resolver != null) {
+            return resolver.removeModel(resolved);
+        } else {
+            return map.remove(resolved);
+        }
+    }
+
+    public <T> T resolveModel(Class<T> modelClass, T unresolved) {
+        // Protect against dependency cycles causing infinite recursion
+        // Save the current unresolved object and check later if we are trying
+        // to resolve the same object again
+        if (unresolved == lastUnresolved) {
+            return unresolved;
+        }
+        lastUnresolved = unresolved;
+        
+        ModelResolver resolver = getModelResolverInstance(unresolved.getClass());
+        if (resolver != null) {
+            Object resolved = resolver.resolveModel(modelClass, unresolved);
+            if (resolved != null && resolved != unresolved) {
+                lastUnresolved = null;
+                return modelClass.cast(resolved);
+            }
+        } else {
+            //FIXME Remove this default resolver, this is currently used to resolve policy declarations
+            // but they should be handled by the contribution import/export mechanism instead of this
+            // defaultResolver hack.
+            if (defaultResolver != null) {
+                Object resolved = defaultResolver.resolveModel(modelClass, unresolved);
+                if (resolved != null && resolved != unresolved) {
+                    lastUnresolved = null;
+                    return modelClass.cast(resolved);
+                }
+            }
+            
+            Object resolved = map.get(unresolved);
+            if (resolved != null) {
+                // Return the resolved object
+                lastUnresolved = null;
+                return modelClass.cast(resolved);
+            }
+        }
+
+        return unresolved;
+    }
+    
+    // FIXME: TUSCANY-2499: temporarily  give access to the defaultResolver to get the jms binding
+    //  use of definitions.xml working while the definitions.xml processing is being refactored
+    public ModelResolver getDefaultModelResolver() {
+        return defaultResolver;
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ModelResolver.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ModelResolver.java
new file mode 100644
index 0000000000..2831bebbc4
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ModelResolver.java
@@ -0,0 +1,69 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+/**
+ * A model resolver, responsible for resolving models in the scope of an
+ * SCA contribution. 
+ * 
+ * SCA Assemblies reference artifacts of a wide variety of types. These
+ * include:
+ * <ul>
+ * <li> Reference from one SCA composite to another SCA composite
+ * <li> Reference to PolicySet files
+ * <li> Reference to interface definition files, either WSDL or Java interfaces
+ * <li> Reference to XSD files
+ * <li> Reference to any of a wide variety of implementation artifact files,
+ * including Java classes, BPEL scripts, C++ DLLs and classes, PHP scripts
+ * </ul>
+ * 
+ * In the SCA assemblies, these various artifacts are referenced using either
+ * QNames or logical URIs. Model resolvers are used to resolve these references
+ * and get the in-memory models representing the referenced artifacts.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface ModelResolver {
+
+    /**
+     * Resolve the model representing an artifact.
+     * 
+     * @param modelClass the type of artifact
+     * @param unresolved the unresolved model
+     * @return the resolved model
+     */
+    <T> T resolveModel(Class<T> modelClass, T unresolved);
+    
+    /**
+     * Add a resolved model.
+     * 
+     * @param resolved The model
+     */
+    void addModel(Object resolved);
+    
+    /**
+     * Remove a resolved model.
+     * 
+     * @param resolved
+     * @return The removed model, or null if the model was not removed
+     */
+    Object removeModel(Object resolved);
+    
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ModelResolverExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ModelResolverExtensionPoint.java
new file mode 100644
index 0000000000..4a25059792
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ModelResolverExtensionPoint.java
@@ -0,0 +1,52 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+
+/**
+ * An extension point for model resolvers
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface ModelResolverExtensionPoint {
+
+    /**
+     * Register a model resolver class using the model type as the key
+     * 
+     * @param modelType The model type
+     * @param resolver The model resolver Class
+     */
+    void addResolver(Class<?> modelType, Class <? extends ModelResolver> resolver);
+    
+    /**
+     * Remove the model resolver class for a specific model type
+     * 
+     * @param modelType The model type
+     */
+    void removeResolver(Class<?> modelType);
+    
+    /**
+     * Retrieve a model resolver class for a specific model type
+     * 
+     * @param modelType The model artifact type
+     * @return The model resolver Class
+     */
+    Class <? extends ModelResolver> getResolver(Class<?> modelType);
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ResolverExtension.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ResolverExtension.java
new file mode 100644
index 0000000000..74f0f2d71d
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ResolverExtension.java
@@ -0,0 +1,45 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+/**
+ * Extension to assembly model implementations to provide a model resolver.
+ *
+ * @version $Rev$ $Date$
+ */
+public interface ResolverExtension {
+
+    /**
+     * Returns the model resolver for the models representing the artifacts
+     * visible in the scope of this contribution.
+     * 
+     * @return The model resolver
+     */
+    ModelResolver getModelResolver();
+    
+    /**
+     * Sets the model resolver for the models representing the artifacts
+     * visible in the scope of this contribution.
+     * 
+     * @param modelResolver The model resolver
+     */
+    void setModelResolver(ModelResolver modelResolver);
+    
+}
\ No newline at end of file
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ResourceReference.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ResourceReference.java
new file mode 100644
index 0000000000..2394f4510b
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/resolver/ResourceReference.java
@@ -0,0 +1,103 @@
+/*

+ * Licensed to the Apache Software Foundation (ASF) under one

+ * or more contributor license agreements.  See the NOTICE file

+ * distributed with this work for additional information

+ * regarding copyright ownership.  The ASF licenses this file

+ * to you under the Apache License, Version 2.0 (the

+ * "License"); you may not use this file except in compliance

+ * with the License.  You may obtain a copy of the License at

+ * 

+ *   http://www.apache.org/licenses/LICENSE-2.0

+ * 

+ * Unless required by applicable law or agreed to in writing,

+ * software distributed under the License is distributed on an

+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+ * KIND, either express or implied.  See the License for the

+ * specific language governing permissions and limitations

+ * under the License.    

+ */

+

+package org.apache.tuscany.sca.contribution.resolver;

+

+import java.net.URL;

+

+/**

+ * A resource URL, which should be used to register resources

+ * with an ArtifactResolver and resolve these resources later.

+ * 

+ * FIXME Don't use as its deprecated, use Artifact instead.

+ *

+ * @version $Rev$ $Date$

+ */

+@Deprecated

+public class ResourceReference {

+    

+    private URL resourceURL;

+    private String resourceName;

+

+    /**

+     * Constructs a new ResourceReference.

+     * 

+     * @param resourceName Name of resource

+     * @param resourceURL  The resource URL

+     */

+    public ResourceReference(String resourceName, URL resourceURL) {

+        this.resourceURL = resourceURL;

+        this.resourceName = resourceName;

+    }

+    

+    /**

+     * Constructs a new ResourceReference.

+     * 

+     * @param resourceName Name of resource

+     */

+    public ResourceReference(String resourceName) {

+        this.resourceName = resourceName;

+    }

+    

+    /**

+     * Get the resource URL.

+     * 

+     * @return The resource URL

+     */

+    public URL getResource() {

+        return resourceURL;

+    }

+    

+    /**

+     * Get the resource name.

+     * 

+     * @return The resource name

+     */

+    public String getResourceName() {

+        return resourceName;

+    }

+    

+    /**

+     * Returns true if the resource reference is unresolved.

+     * 

+     * @return Whether or not the resource has been resolved

+     */

+    public boolean isUnresolved() {

+        return resourceURL == null;

+    }

+

+    @Override

+    public int hashCode() {

+        return resourceName.hashCode();

+    }

+    

+    @Override

+    public boolean equals(Object obj) {

+        if (obj == this) {

+            return true;

+        } else {

+            if (obj instanceof ResourceReference) {

+                return resourceName.equals(((ResourceReference)obj).resourceName);

+            } else {

+                return false;

+            }

+        }

+    }

+

+}

diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/ContributionScanner.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/ContributionScanner.java
new file mode 100644
index 0000000000..4e71e1ac30
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/ContributionScanner.java
@@ -0,0 +1,67 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.scanner;
+
+import java.io.IOException;
+import java.net.URL;
+import java.util.List;
+
+import org.apache.tuscany.sca.contribution.processor.ContributionException;
+import org.apache.tuscany.sca.contribution.processor.ContributionReadException;
+
+/**
+ * Interface for contribution package scanners
+ * 
+ * Contribution scanners understand the format of the contribution and how to get the
+ * artifacts in the contribution.
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface ContributionScanner {
+    
+    /**
+     * Returns the type of package supported by this package scanner.
+     * 
+     * @return the package type
+     */
+    String getContributionType();
+
+    /**
+     * Returns a list of artifacts in the contribution.
+     * 
+     * @param contributionURL Contribution URL
+     * @return List of artifact URIs
+     * @throws ContributionException
+     * @throws IOException
+     */
+    List<String> getArtifacts(URL contributionURL) throws ContributionReadException;
+
+    /**
+     * Return the URL for an artifact in the contribution.
+     * 
+     * This is needed for archives such as jar files that have specific URL schemes
+     * for the artifacts they contain.
+     * 
+     * @param contributionURL Contribution URL
+     * @param artifact The relative URI for the artifact
+     * @return The artifact URL
+     */
+    URL getArtifactURL(URL contributionURL, String artifact) throws ContributionReadException;
+
+}
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/ContributionScannerExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/ContributionScannerExtensionPoint.java
new file mode 100644
index 0000000000..1ca9def4ea
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/ContributionScannerExtensionPoint.java
@@ -0,0 +1,50 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+package org.apache.tuscany.sca.contribution.scanner;
+
+/**
+ * An extension point for contribution scanners
+ * 
+ * @version $Rev$ $Date$
+ */
+public interface ContributionScannerExtensionPoint {
+    
+    /**
+     * Add a ContributionScanner using the contribution type as the key.
+     * 
+     * @param scanner The contribution scanner
+     */
+    void addContributionScanner(ContributionScanner scanner);
+    
+    /**
+     * Remove a ContributionScanner.
+     * 
+     * @param scanner The contribution scanner
+     */
+    void removeContributionScanner(ContributionScanner scanner);
+    
+    /**
+     * Returns the ContributionScanner for the given contribution type.
+     * 
+     * @param contributionType The contribution type
+     * @return The contribution scanner
+     */
+    ContributionScanner getContributionScanner(String contributionType);
+    
+}
\ No newline at end of file
diff --git a/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/DefaultContributionScannerExtensionPoint.java b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/DefaultContributionScannerExtensionPoint.java
new file mode 100644
index 0000000000..cf3c77d5eb
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/java/org/apache/tuscany/sca/contribution/scanner/DefaultContributionScannerExtensionPoint.java
@@ -0,0 +1,125 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.scanner;
+
+import java.io.IOException;
+import java.lang.reflect.Constructor;
+import java.net.URL;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import org.apache.tuscany.sca.contribution.processor.ContributionReadException;
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+
+/**
+ * Default implementation of a contribution scanner extension point.
+ * 
+ * @version $Rev$ $Date$
+ */
+public class DefaultContributionScannerExtensionPoint implements ContributionScannerExtensionPoint {
+
+    private Map<String, ContributionScanner> scanners = new HashMap<String, ContributionScanner>();
+    private boolean loaded;
+
+    public DefaultContributionScannerExtensionPoint() {
+    }
+
+    public void addContributionScanner(ContributionScanner scanner) {
+        scanners.put(scanner.getContributionType(), scanner);
+    }
+
+    public void removeContributionScanner(ContributionScanner scanner) {
+        scanners.remove(scanner.getContributionType());
+    }
+
+    public ContributionScanner getContributionScanner(String contentType) {
+        loadScanners();
+        return scanners.get(contentType);
+    }
+
+    private void loadScanners() {
+        if (loaded)
+            return;
+
+        // Get the scanner service declarations
+        Set<ServiceDeclaration> scannerDeclarations; 
+        try {
+            scannerDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations(ContributionScanner.class.getName());
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
+        
+        for (ServiceDeclaration scannerDeclaration: scannerDeclarations) {
+            Map<String, String> attributes = scannerDeclaration.getAttributes();
+            
+            // Load a URL artifact scanner
+            String contributionType = attributes.get("type");
+            
+            // Create a scanner wrapper and register it
+            ContributionScanner scanner = new LazyContributionScanner(contributionType, scannerDeclaration);
+            addContributionScanner(scanner);
+        }
+        
+        loaded = true;
+    }
+
+    /**
+     * A facade for contribution scanners.
+     */
+    private static class LazyContributionScanner implements ContributionScanner {
+        
+        private ServiceDeclaration scannerDeclaration;
+        private String contributionType;
+        private ContributionScanner scanner;
+        
+        private LazyContributionScanner(String contributionType, ServiceDeclaration scannerDeclaration) {
+            this.scannerDeclaration = scannerDeclaration;
+            this.contributionType = contributionType;
+        }
+
+        public URL getArtifactURL(URL contributionSourceURL, String artifact) throws ContributionReadException {
+            return getScanner().getArtifactURL(contributionSourceURL, artifact);
+        }
+
+        public List<String> getArtifacts(URL contributionSourceURL) throws ContributionReadException {
+            return getScanner().getArtifacts(contributionSourceURL);
+        }
+
+        public String getContributionType() {
+            return contributionType;
+        }
+        
+        private ContributionScanner getScanner() {
+            if (scanner == null) {
+                try {
+                    Class<ContributionScanner> scannerClass = (Class<ContributionScanner>)scannerDeclaration.loadClass();
+                    Constructor<ContributionScanner> constructor = scannerClass.getConstructor();
+                    scanner = constructor.newInstance();
+                } catch (Exception e) {
+                    throw new IllegalStateException(e);
+                }
+            }
+            return scanner;
+        }
+    }
+}
diff --git a/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.ContributionFactory b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.ContributionFactory
new file mode 100644
index 0000000000..bcc346d9f8
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.ContributionFactory
@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one

+# or more contributor license agreements.  See the NOTICE file

+# distributed with this work for additional information

+# regarding copyright ownership.  The ASF licenses this file

+# to you under the Apache License, Version 2.0 (the

+# "License"); you may not use this file except in compliance

+# with the License.  You may obtain a copy of the License at

+# 

+#   http://www.apache.org/licenses/LICENSE-2.0

+# 

+# Unless required by applicable law or agreed to in writing,

+# software distributed under the License is distributed on an

+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+# KIND, either express or implied.  See the License for the

+# specific language governing permissions and limitations

+# under the License. 

+

+org.apache.tuscany.sca.contribution.DefaultContributionFactory
\ No newline at end of file
diff --git a/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.ContributionPostProcessorExtensionPoint b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.ContributionPostProcessorExtensionPoint
new file mode 100644
index 0000000000..9e6433ba6c
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.ContributionPostProcessorExtensionPoint
@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one

+# or more contributor license agreements.  See the NOTICE file

+# distributed with this work for additional information

+# regarding copyright ownership.  The ASF licenses this file

+# to you under the Apache License, Version 2.0 (the

+# "License"); you may not use this file except in compliance

+# with the License.  You may obtain a copy of the License at

+# 

+#   http://www.apache.org/licenses/LICENSE-2.0

+# 

+# Unless required by applicable law or agreed to in writing,

+# software distributed under the License is distributed on an

+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+# KIND, either express or implied.  See the License for the

+# specific language governing permissions and limitations

+# under the License. 

+

+org.apache.tuscany.sca.contribution.processor.DefaultContributionPostProcessorExtensionPoint

diff --git a/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.StAXArtifactProcessorExtensionPoint b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.StAXArtifactProcessorExtensionPoint
new file mode 100644
index 0000000000..8ea5fc0a7e
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.StAXArtifactProcessorExtensionPoint
@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one

+# or more contributor license agreements.  See the NOTICE file

+# distributed with this work for additional information

+# regarding copyright ownership.  The ASF licenses this file

+# to you under the Apache License, Version 2.0 (the

+# "License"); you may not use this file except in compliance

+# with the License.  You may obtain a copy of the License at

+# 

+#   http://www.apache.org/licenses/LICENSE-2.0

+# 

+# Unless required by applicable law or agreed to in writing,

+# software distributed under the License is distributed on an

+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+# KIND, either express or implied.  See the License for the

+# specific language governing permissions and limitations

+# under the License. 

+

+org.apache.tuscany.sca.contribution.processor.DefaultStAXArtifactProcessorExtensionPoint

diff --git a/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.StAXAttributeProcessorExtensionPoint b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.StAXAttributeProcessorExtensionPoint
new file mode 100644
index 0000000000..607725bcfe
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.StAXAttributeProcessorExtensionPoint
@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one

+# or more contributor license agreements.  See the NOTICE file

+# distributed with this work for additional information

+# regarding copyright ownership.  The ASF licenses this file

+# to you under the Apache License, Version 2.0 (the

+# "License"); you may not use this file except in compliance

+# with the License.  You may obtain a copy of the License at

+# 

+#   http://www.apache.org/licenses/LICENSE-2.0

+# 

+# Unless required by applicable law or agreed to in writing,

+# software distributed under the License is distributed on an

+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+# KIND, either express or implied.  See the License for the

+# specific language governing permissions and limitations

+# under the License. 

+

+org.apache.tuscany.sca.contribution.processor.DefaultStAXAttributeProcessorExtensionPoint

diff --git a/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.URLArtifactProcessorExtensionPoint b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.URLArtifactProcessorExtensionPoint
new file mode 100644
index 0000000000..9d78ca93d0
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.URLArtifactProcessorExtensionPoint
@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one

+# or more contributor license agreements.  See the NOTICE file

+# distributed with this work for additional information

+# regarding copyright ownership.  The ASF licenses this file

+# to you under the Apache License, Version 2.0 (the

+# "License"); you may not use this file except in compliance

+# with the License.  You may obtain a copy of the License at

+# 

+#   http://www.apache.org/licenses/LICENSE-2.0

+# 

+# Unless required by applicable law or agreed to in writing,

+# software distributed under the License is distributed on an

+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+# KIND, either express or implied.  See the License for the

+# specific language governing permissions and limitations

+# under the License. 

+

+org.apache.tuscany.sca.contribution.processor.DefaultURLArtifactProcessorExtensionPoint

diff --git a/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.ValidatingXMLInputFactory b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.ValidatingXMLInputFactory
new file mode 100644
index 0000000000..f2856cb259
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.ValidatingXMLInputFactory
@@ -0,0 +1,17 @@
+# Licensed to the Apache Software Foundation (ASF) under one

+# or more contributor license agreements.  See the NOTICE file

+# distributed with this work for additional information

+# regarding copyright ownership.  The ASF licenses this file

+# to you under the Apache License, Version 2.0 (the

+# "License"); you may not use this file except in compliance

+# with the License.  You may obtain a copy of the License at

+# 

+#   http://www.apache.org/licenses/LICENSE-2.0

+# 

+# Unless required by applicable law or agreed to in writing,

+# software distributed under the License is distributed on an

+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+# KIND, either express or implied.  See the License for the

+# specific language governing permissions and limitations

+# under the License. 

+org.apache.tuscany.sca.contribution.processor.DefaultValidatingXMLInputFactory
\ No newline at end of file
diff --git a/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.ValidationSchemaExtensionPoint b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.ValidationSchemaExtensionPoint
new file mode 100644
index 0000000000..ae6e876df6
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.processor.ValidationSchemaExtensionPoint
@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one

+# or more contributor license agreements.  See the NOTICE file

+# distributed with this work for additional information

+# regarding copyright ownership.  The ASF licenses this file

+# to you under the Apache License, Version 2.0 (the

+# "License"); you may not use this file except in compliance

+# with the License.  You may obtain a copy of the License at

+# 

+#   http://www.apache.org/licenses/LICENSE-2.0

+# 

+# Unless required by applicable law or agreed to in writing,

+# software distributed under the License is distributed on an

+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+# KIND, either express or implied.  See the License for the

+# specific language governing permissions and limitations

+# under the License. 

+

+org.apache.tuscany.sca.contribution.processor.DefaultValidationSchemaExtensionPoint

diff --git a/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.resolver.ModelResolverExtensionPoint b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.resolver.ModelResolverExtensionPoint
new file mode 100644
index 0000000000..4bb65e55e7
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.resolver.ModelResolverExtensionPoint
@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one

+# or more contributor license agreements.  See the NOTICE file

+# distributed with this work for additional information

+# regarding copyright ownership.  The ASF licenses this file

+# to you under the Apache License, Version 2.0 (the

+# "License"); you may not use this file except in compliance

+# with the License.  You may obtain a copy of the License at

+# 

+#   http://www.apache.org/licenses/LICENSE-2.0

+# 

+# Unless required by applicable law or agreed to in writing,

+# software distributed under the License is distributed on an

+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+# KIND, either express or implied.  See the License for the

+# specific language governing permissions and limitations

+# under the License. 

+

+org.apache.tuscany.sca.contribution.resolver.DefaultModelResolverExtensionPoint

diff --git a/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.scanner.ContributionScannerExtensionPoint b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.scanner.ContributionScannerExtensionPoint
new file mode 100644
index 0000000000..727f8f6ce7
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/META-INF/services/org.apache.tuscany.sca.contribution.scanner.ContributionScannerExtensionPoint
@@ -0,0 +1,18 @@
+# Licensed to the Apache Software Foundation (ASF) under one

+# or more contributor license agreements.  See the NOTICE file

+# distributed with this work for additional information

+# regarding copyright ownership.  The ASF licenses this file

+# to you under the Apache License, Version 2.0 (the

+# "License"); you may not use this file except in compliance

+# with the License.  You may obtain a copy of the License at

+# 

+#   http://www.apache.org/licenses/LICENSE-2.0

+# 

+# Unless required by applicable law or agreed to in writing,

+# software distributed under the License is distributed on an

+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+# KIND, either express or implied.  See the License for the

+# specific language governing permissions and limitations

+# under the License. 

+

+org.apache.tuscany.sca.contribution.scanner.DefaultContributionScannerExtensionPoint

diff --git a/java/sca/modules/contribution/src/main/resources/contribution-validation-messages.properties b/java/sca/modules/contribution/src/main/resources/contribution-validation-messages.properties
new file mode 100644
index 0000000000..4f9f85048e
--- /dev/null
+++ b/java/sca/modules/contribution/src/main/resources/contribution-validation-messages.properties
@@ -0,0 +1,34 @@
+#
+#
+#    Licensed to the Apache Software Foundation (ASF) under one
+#    or more contributor license agreements. See the NOTICE file
+#    distributed with this work for additional information
+#    regarding copyright ownership. The ASF licenses this file
+#    to you under the Apache License, Version 2.0 (the
+#    "License"); you may not use this file except in compliance
+#    with the License. You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing,
+#    software distributed under the License is distributed on an
+#    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+#    KIND, either express or implied. See the License for the
+#    specific language governing permissions and limitations
+#    under the License.
+#
+#
+SchemaError = XMLSchema validation error occured in: {0} ,line = {1}, column = {2}, Message = {3}
+SchemaFatalError = XMLSchema validation fatal error occured in: {0} ,line = {1}, column = {2}, Message = {3}
+SchemaWarning = XMLSchema validation warning occured in: {0} ,line = {1}, column = {2}, Message = {3}
+UnsupportedPackageTypeException = Unsupported contribution package type: {0}
+ElementCannotBeProcessed = Element {0} cannot be processed. ({1})
+AttributeCannotBeProcessed = Attribute {0} cannot be processed. ({1})
+NoStaxProcessor = No StAX processor is configured to handle {0}
+ContributionWriteException = ContributionWriteException occured due to :
+ContributionReadException = ContributionReadException occured due to :
+UnrecognizedElementException = Unrecognized Element : {0}
+IllegalArgumentException = Invalid qname: {0}
+PrivilegedActionException = PrivilegedActionException occured due to : 
+AttributeCannotBeProcessed = Attribute {0} cannot be processed. ({1})
+
diff --git a/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/processor/URLartifactProcessorExtensionPointTestCase.java b/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/processor/URLartifactProcessorExtensionPointTestCase.java
new file mode 100644
index 0000000000..14b6b956da
--- /dev/null
+++ b/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/processor/URLartifactProcessorExtensionPointTestCase.java
@@ -0,0 +1,113 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.processor;
+
+import static junit.framework.Assert.assertNotNull;
+
+import java.net.URI;
+import java.net.URL;
+
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.core.DefaultExtensionPointRegistry;
+import org.apache.tuscany.sca.core.ExtensionPointRegistry;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+/**
+ * URL Artifact Processor Extension Point test case
+ * Verifies the right registration and lookup for processors that handle filename and file types
+ * 
+ * @version $Rev$ $Date$
+ */
+public class URLartifactProcessorExtensionPointTestCase {
+
+    private static URLArtifactProcessorExtensionPoint artifactProcessors;
+
+    @BeforeClass
+    public static void setUp() throws Exception {
+        ExtensionPointRegistry extensionPoints = new DefaultExtensionPointRegistry();
+        artifactProcessors = new DefaultURLArtifactProcessorExtensionPoint(extensionPoints);
+        artifactProcessors.addArtifactProcessor(new FileTypeArtifactProcessor());
+        artifactProcessors.addArtifactProcessor(new FileNameArtifactProcessor());
+    }
+
+    @Test
+    public final void testFileTypeProcessor() {
+        assertNotNull(artifactProcessors.getProcessor(".m1"));
+    }
+
+    @Test
+    public final void testFileNameProcessor() {
+        assertNotNull(artifactProcessors.getProcessor("file.m2"));
+
+    }
+
+    /**
+     * Internal mock classes
+     *
+     */
+
+    private class M1 {
+    }
+
+    private class M2 {
+    }
+
+    private static class FileTypeArtifactProcessor implements URLArtifactProcessor<M1> {
+        public FileTypeArtifactProcessor() {
+        }
+
+        public M1 read(URL contributionURL, URI uri, URL url) throws ContributionReadException {
+            return null;
+        }
+
+        public void resolve(M1 m1, ModelResolver resolver) throws ContributionResolveException {
+        }
+
+        public String getArtifactType() {
+            return ".m1";
+        }
+
+        public Class<M1> getModelType() {
+            return M1.class;
+        }
+    }
+
+    private static class FileNameArtifactProcessor implements URLArtifactProcessor<M2> {
+        public FileNameArtifactProcessor() {
+        }
+
+        public M2 read(URL contributionURL, URI uri, URL url) throws ContributionReadException {
+            return null;
+        }
+
+        public void resolve(M2 m2, ModelResolver resolver) throws ContributionResolveException {
+        }
+
+        public String getArtifactType() {
+            return "file.m2";
+        }
+
+        public Class<M2> getModelType() {
+            return M2.class;
+        }
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/resolver/DefaultModelResolverTestCase.java b/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/resolver/DefaultModelResolverTestCase.java
new file mode 100644
index 0000000000..f5b04f503c
--- /dev/null
+++ b/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/resolver/DefaultModelResolverTestCase.java
@@ -0,0 +1,91 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+import static junit.framework.Assert.assertTrue;
+
+import org.apache.tuscany.sca.contribution.Artifact;
+import org.apache.tuscany.sca.contribution.ContributionFactory;
+import org.apache.tuscany.sca.contribution.DefaultContributionFactory;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Test the default model resolver implementation.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultModelResolverTestCase {
+
+    private ModelResolver resolver;
+    private ContributionFactory factory;
+
+    @Before
+    public void setUp() throws Exception {
+        resolver = new DefaultModelResolver();
+        factory = new DefaultContributionFactory();
+    }
+
+    @Test
+    public void testResolved() {
+        Model a = new Model("a");
+        resolver.addModel(a);
+        Model x = new Model("a");
+        x = resolver.resolveModel(Model.class, x);
+        assertTrue(x == a);
+    }
+
+    @Test
+    public void testUnresolved() {
+        Model x = new Model("a");
+        Model y = resolver.resolveModel(Model.class, x);
+        assertTrue(x == y);
+    }
+
+    @Test
+    public void testResolvedArtifact() {
+        Artifact artifact = factory.createArtifact();
+        artifact.setURI("foo/bar");
+        resolver.addModel(artifact);
+        Artifact x = factory.createArtifact();
+        x.setURI("foo/bar");
+        x = resolver.resolveModel(Artifact.class, x);
+        assertTrue(x == artifact);
+    }
+
+    class Model {
+        private String name;
+
+        Model(String name) {
+            this.name = name;
+        }
+
+        @Override
+        public int hashCode() {
+            return name.hashCode();
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            return name.equals(((Model)obj).name);
+        }
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/resolver/ExtensibleModelResolverTestCase.java b/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/resolver/ExtensibleModelResolverTestCase.java
new file mode 100644
index 0000000000..e4082b3b85
--- /dev/null
+++ b/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/resolver/ExtensibleModelResolverTestCase.java
@@ -0,0 +1,134 @@
+/*
+* Licensed to the Apache Software Foundation (ASF) under one
+* or more contributor license agreements.  See the NOTICE file
+* distributed with this work for additional information
+* regarding copyright ownership.  The ASF licenses this file
+* to you under the Apache License, Version 2.0 (the
+* "License"); you may not use this file except in compliance
+* with the License.  You may obtain a copy of the License at
+* 
+*   http://www.apache.org/licenses/LICENSE-2.0
+* 
+* Unless required by applicable law or agreed to in writing,
+* software distributed under the License is distributed on an
+* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+* KIND, either express or implied.  See the License for the
+* specific language governing permissions and limitations
+* under the License.    
+*/
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+import static junit.framework.Assert.assertTrue;
+
+import org.apache.tuscany.sca.contribution.Artifact;
+import org.apache.tuscany.sca.contribution.ContributionFactory;
+import org.apache.tuscany.sca.contribution.DefaultContributionFactory;
+import org.apache.tuscany.sca.core.DefaultExtensionPointRegistry;
+import org.apache.tuscany.sca.core.DefaultFactoryExtensionPoint;
+import org.apache.tuscany.sca.core.FactoryExtensionPoint;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Test DefaultArtifactResolver.
+ *
+ * @version $Rev$ $Date$
+ */
+public class ExtensibleModelResolverTestCase {
+    private ExtensibleModelResolver resolver;
+
+    private ContributionFactory factory;
+
+    @Before
+    public void setUp() throws Exception {
+
+        ModelResolverExtensionPoint resolvers = new DefaultModelResolverExtensionPoint();
+        resolvers.addResolver(Model.class, TestModelResolver.class);
+
+        FactoryExtensionPoint factories = new DefaultFactoryExtensionPoint(new DefaultExtensionPointRegistry());
+
+        resolver = new ExtensibleModelResolver(null, resolvers, factories, null);
+
+        factory = new DefaultContributionFactory();
+    }
+
+    @Test
+    public void testResolvedDefault() {
+        OtherModel a = new OtherModel("a");
+        resolver.addModel(a);
+        OtherModel x = new OtherModel("a");
+        x = resolver.resolveModel(OtherModel.class, x);
+        assertTrue(x == a);
+    }
+
+    @Test
+    public void testResolvedRegisteredClass() {
+        Model a = new Model("a");
+        resolver.addModel(a);
+        Model x = new Model("a");
+        x = resolver.resolveModel(Model.class, x);
+        assertTrue(x == a);
+    }
+
+    @Test
+    public void testUnresolvedDefault() {
+        OtherModel x = new OtherModel("a");
+        OtherModel y = resolver.resolveModel(OtherModel.class, x);
+        assertTrue(x == y);
+    }
+
+    @Test
+    public void testUnresolved() {
+        Model x = new Model("a");
+        Model y = resolver.resolveModel(Model.class, x);
+        assertTrue(x == y);
+    }
+
+    @Test
+    public void testResolvedArtifact() {
+        Artifact artifact = factory.createArtifact();
+        artifact.setURI("foo/bar");
+        resolver.addModel(artifact);
+        Artifact x = factory.createArtifact();
+        x.setURI("foo/bar");
+        x = resolver.resolveModel(Artifact.class, x);
+        assertTrue(x == artifact);
+    }
+
+    private class Model {
+        private String name;
+
+        Model(String name) {
+            this.name = name;
+        }
+
+        @Override
+        public int hashCode() {
+            return name.hashCode();
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            return name.equals(((Model)obj).name);
+        }
+    }
+
+    private class OtherModel {
+        private String name;
+
+        OtherModel(String name) {
+            this.name = name;
+        }
+
+        @Override
+        public int hashCode() {
+            return name.hashCode();
+        }
+
+        @Override
+        public boolean equals(Object obj) {
+            return name.equals(((OtherModel)obj).name);
+        }
+    }
+}
diff --git a/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/resolver/TestModelResolver.java b/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/resolver/TestModelResolver.java
new file mode 100644
index 0000000000..cd586d3b2c
--- /dev/null
+++ b/java/sca/modules/contribution/src/test/java/org/apache/tuscany/sca/contribution/resolver/TestModelResolver.java
@@ -0,0 +1,58 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.    
+ */
+
+package org.apache.tuscany.sca.contribution.resolver;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.tuscany.sca.contribution.Contribution;
+import org.apache.tuscany.sca.core.FactoryExtensionPoint;
+
+/**
+ * A test implementation of a model resolver, based on a map.
+ * 
+ * @version $Rev$ $Date$
+ */
+public class TestModelResolver implements ModelResolver {
+
+    private Map<Object, Object> map = new HashMap<Object, Object>();
+
+    public TestModelResolver(Contribution contribution, FactoryExtensionPoint modelFactories) {
+    }
+
+    public <T> T resolveModel(Class<T> modelClass, T unresolved) {
+        Object resolved = map.get(unresolved);
+        if (resolved != null) {
+            // Return the resolved object
+            return modelClass.cast(resolved);
+        }
+        // Return the unresolved object
+        return unresolved;
+    }
+
+    public void addModel(Object resolved) {
+        map.put(resolved, resolved);
+    }
+
+    public Object removeModel(Object resolved) {
+        return map.remove(resolved);
+    }
+
+}
diff --git a/java/sca/modules/contribution/src/test/resources/deployables/sample-calculator.jar b/java/sca/modules/contribution/src/test/resources/deployables/sample-calculator.jar
new file mode 100644
index 0000000000..0ca3a1b781
--- /dev/null
+++ b/java/sca/modules/contribution/src/test/resources/deployables/sample-calculator.jar
diff --git a/java/sca/modules/contribution/src/test/resources/repository/sample-calculator.jar b/java/sca/modules/contribution/src/test/resources/repository/sample-calculator.jar
new file mode 100644
index 0000000000..9c46c679d2
--- /dev/null
+++ b/java/sca/modules/contribution/src/test/resources/repository/sample-calculator.jar
diff --git a/java/sca/modules/contribution/src/test/resources/test.composite b/java/sca/modules/contribution/src/test/resources/test.composite
new file mode 100644
index 0000000000..1e09549194
--- /dev/null
+++ b/java/sca/modules/contribution/src/test/resources/test.composite
@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="UTF-8"?>

+<!--

+ * Licensed to the Apache Software Foundation (ASF) under one

+ * or more contributor license agreements.  See the NOTICE file

+ * distributed with this work for additional information

+ * regarding copyright ownership.  The ASF licenses this file

+ * to you under the Apache License, Version 2.0 (the

+ * "License"); you may not use this file except in compliance

+ * with the License.  You may obtain a copy of the License at

+ *

+ *   http://www.apache.org/licenses/LICENSE-2.0

+ *

+ * Unless required by applicable law or agreed to in writing,

+ * software distributed under the License is distributed on an

+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY

+ * KIND, either express or implied.  See the License for the

+ * specific language governing permissions and limitations

+ * under the License.

+-->

+<composite>

+    This file just needs to exist

+</composite>
\ No newline at end of file
diff --git a/java/sca/modules/contribution/src/test/resources/test.ext b/java/sca/modules/contribution/src/test/resources/test.ext
new file mode 100644
index 0000000000..e69de29bb2
--- /dev/null
+++ b/java/sca/modules/contribution/src/test/resources/test.ext