Create 2.0-M2 release branch

git-svn-id: http://svn.us.apache.org/repos/asf/tuscany@757361 13f79535-47bb-0310-9956-ffa450edef68

6 files changed, 762 insertions, 0 deletions

diff --git a/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/BundleReference.java b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/BundleReference.java
new file mode 100644
index 0000000000..3f82f6fb17
--- /dev/null
+++ b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/BundleReference.java
@@ -0,0 +1,136 @@
+/*
+ * 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.osgi;
+
+import org.osgi.framework.Bundle;
+import org.osgi.framework.Constants;
+
+/**
+ * A reference to an OSGi bundle
+ *
+ * @version $Rev$ $Date$
+ */
+public class BundleReference {
+
+    /**
+     * The bundle.
+     */
+    private Bundle bundle;
+
+    /**
+     * The bundle version.
+     */
+    private String version;
+
+    /**
+     * The bundle name and version.
+     */
+    private String symbolicName;
+
+    /**
+     * Constructs a new BundleReference.
+     * 
+     * @param bundle
+     */
+    public BundleReference(Bundle bundle) {
+        this.bundle = bundle;
+        this.symbolicName = bundle.getSymbolicName();
+        this.version = (String)bundle.getHeaders().get(Constants.BUNDLE_VERSION);
+    }
+
+    /**
+     * Constructs a new BundleReference.
+     * 
+     * @param bundleSymbolicName The bundle symbolic name
+     * @param bundleVersion The bundle version
+     */
+    public BundleReference(String bundleSymbolicName, String bundleVersion) {
+        this.version = bundleVersion;
+        this.symbolicName = bundleSymbolicName;
+    }
+
+    /**
+     * Get the referenced bundle.
+     * 
+     * @return The referenced bundle
+     */
+    public Bundle getBundle() {
+        return bundle;
+    }
+
+    /**
+     * Get the referenced bundle version.
+     * 
+     * @return The bundle version
+     */
+    public String getVersion() {
+        return version;
+    }
+
+    /**
+     * Get the referenced bundle name and version.
+     * 
+     * @return The bundle name
+     */
+    public String getSymbolicName() {
+        return symbolicName;
+    }
+
+    /**
+     * Returns true if the bundle reference is unresolved.
+     * 
+     * @return Whether or not the bundle has been resolved
+     */
+    public boolean isUnresolved() {
+        return bundle == null;
+    }
+
+    @Override
+    public int hashCode() {
+        final int prime = 31;
+        int result = 1;
+        result = prime * result + ((symbolicName == null) ? 0 : symbolicName.hashCode());
+        result = prime * result + ((version == null) ? 0 : version.hashCode());
+        return result;
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj)
+            return true;
+        if (obj == null)
+            return false;
+        if (getClass() != obj.getClass())
+            return false;
+        BundleReference other = (BundleReference)obj;
+        if (symbolicName == null) {
+            if (other.symbolicName != null)
+                return false;
+        } else if (!symbolicName.equals(other.symbolicName))
+            return false;
+        if (version == null) {
+            if (other.version != null)
+                return false;
+        } else if (!version.equals(other.version))
+            return false;
+        return true;
+    }
+
+}
diff --git a/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleActivator.java b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleActivator.java
new file mode 100644
index 0000000000..ac7ff7b4ea
--- /dev/null
+++ b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleActivator.java
@@ -0,0 +1,151 @@
+/*
+ * 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.osgi.impl;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.util.jar.JarInputStream;
+import java.util.jar.Manifest;
+
+import org.osgi.framework.Bundle;
+import org.osgi.framework.BundleActivator;
+import org.osgi.framework.BundleContext;
+import org.osgi.framework.BundleException;
+import org.osgi.framework.Constants;
+
+/**
+ * The Bundle Activator that receives the BundleContext
+ */
+public class OSGiBundleActivator implements BundleActivator {
+    private static BundleContext bundleContext;
+
+    public static BundleContext getBundleContext() {
+        return bundleContext;
+    }
+
+    public void start(BundleContext context) throws Exception {
+        bundleContext = context;
+    }
+
+    public void stop(BundleContext context) throws Exception {
+        bundleContext = null;
+    }
+
+    public static Bundle findBundle(URL bundleURL) {
+        if (bundleContext == null) {
+            return null;
+        }
+        Bundle[] installedBundles = bundleContext.getBundles();
+        for (Bundle bundle : installedBundles) {
+            URL root = bundle.getEntry("/");
+            if (root != null && root.getHost() != null && root.getHost().equals(bundleURL.getHost())) {
+                return bundle;
+            }
+        }
+        return null;
+    }
+
+    public static Bundle findBundle(String symbolicName, String version) {
+        if (bundleContext == null) {
+            return null;
+        }
+        Bundle[] bundles = bundleContext.getBundles();
+        if (version == null) {
+            version = "0.0.0";
+        }
+        for (Bundle b : bundles) {
+            String v = (String)b.getHeaders().get(Constants.BUNDLE_VERSION);
+            if (v == null) {
+                v = "0.0.0";
+            }
+            if (b.getSymbolicName().equals(symbolicName) && (version.equals("0.0.0") || v.equals(version))) {
+                return b;
+            }
+        }
+        return null;
+    }
+
+    public static Bundle installBundle(String location, InputStream is) throws BundleException {
+        getBundleContext();
+        return bundleContext.installBundle(location, is);
+    }
+
+    public static Bundle installBundle(String location) throws BundleException, IOException {
+        getBundleContext();
+
+        URL url = new URL(location);
+        Bundle bundle = null;
+        InputStream is = url.openStream();
+        JarInputStream jar = new JarInputStream(is);
+
+        Manifest manifest = jar.getManifest();
+        jar.close();
+        if (manifest != null) {
+            String symbolicName = manifest.getMainAttributes().getValue(Constants.BUNDLE_SYMBOLICNAME);
+            String version = manifest.getMainAttributes().getValue(Constants.BUNDLE_VERSION);
+            if (symbolicName != null) {
+                bundle = findBundle(symbolicName, version);
+                if (bundle != null) {
+                    return bundle;
+                }
+            } else {
+                return null;
+            }
+        } else {
+            return null;
+        }
+        try {
+            is = url.openStream();
+            bundle = bundleContext.installBundle(location, is);
+        } finally {
+            is.close();
+        }
+        return bundle;
+    }
+
+    public static Bundle findBundleByLocation(String bundleLocation) {
+        if (bundleContext != null) {
+            Bundle[] installedBundles = bundleContext.getBundles();
+            for (Bundle bundle : installedBundles) {
+                if (bundle.getLocation().equals(bundleLocation))
+                    return bundle;
+            }
+        }
+        return null;
+    }
+
+    public static Bundle findBundle(String bundleLocation) {
+        if (bundleContext != null) {
+            if (bundleLocation.startsWith("bundle:") || bundleLocation.startsWith("bundleresource:")) {
+                try {
+                    return findBundle(new URL(bundleLocation));
+                } catch (MalformedURLException e) {
+                    // ignore
+                }
+            } else {
+                return findBundleByLocation(bundleLocation);
+            }
+        }
+        return null;
+    }
+
+}
diff --git a/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleContributionScanner.java b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleContributionScanner.java
new file mode 100644
index 0000000000..d64d2ec46c
--- /dev/null
+++ b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleContributionScanner.java
@@ -0,0 +1,153 @@
+/*

+ * 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.osgi.impl;

+

+import java.io.IOException;

+import java.io.InputStream;

+import java.net.URL;

+import java.util.ArrayList;

+import java.util.Enumeration;

+import java.util.HashSet;

+import java.util.List;

+import java.util.Set;

+import java.util.jar.JarEntry;

+import java.util.jar.JarInputStream;

+

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

+import org.apache.tuscany.sca.contribution.processor.ContributionException;

+import org.apache.tuscany.sca.contribution.processor.ContributionReadException;

+import org.apache.tuscany.sca.contribution.scanner.ContributionScanner;

+import org.osgi.framework.Bundle;

+

+/**

+ * Bundle Contribution package processor.

+ *

+ * @version $Rev$ $Date$

+ */

+public class OSGiBundleContributionScanner implements ContributionScanner {

+

+    public OSGiBundleContributionScanner() {

+    }

+

+    public String getContributionType() {

+        return PackageType.BUNDLE;

+    }

+

+    public URL getArtifactURL(URL sourceURL, String artifact) throws ContributionReadException {

+        Bundle bundle = null;

+        try {

+            bundle = OSGiBundleActivator.findBundle(sourceURL);

+            if (bundle != null) {

+                URL url = bundle.getResource(artifact);

+                if (url == null)

+                    System.out.println("Could not load resource " + artifact);

+                return url;

+            }

+        } catch (Exception e) {

+        }

+        return null;

+    }

+    

+    public List<String> getJarArtifacts(URL packageSourceURL, InputStream inputStream) throws ContributionException,

+    IOException {

+    if (packageSourceURL == null) {

+        throw new IllegalArgumentException("Invalid null package source URL.");

+    }

+

+    if (inputStream == null) {

+        throw new IllegalArgumentException("Invalid null source inputstream.");

+    }

+

+    // Assume the root is a jar file

+    JarInputStream jar = new JarInputStream(inputStream);

+    try {

+        Set<String> names = new HashSet<String>();

+        while (true) {

+            JarEntry entry = jar.getNextJarEntry();

+            if (entry == null) {

+                // EOF

+                break;

+            }

+

+            // FIXME: Maybe we should externalize the filter as a property

+            String name = entry.getName(); 

+            if (!name.startsWith(".") && !entry.isDirectory()) {

+                

+                // Trim trailing /

+                if (name.endsWith("/")) {

+                    name = name.substring(0, name.length() - 1);

+                }

+

+                // Add the entry name

+                if (!names.contains(name) && name.length() > 0) {

+                    names.add(name);

+                    

+                }

+            }

+        }

+        

+        // Return list of URIs

+        List<String> artifacts = new ArrayList<String>();

+        for (String name: names) {

+            artifacts.add(name);

+        }

+        return artifacts;

+        

+    } finally {

+        jar.close();

+    }

+}

+

+    public List<String> getArtifacts(URL packageSourceURL) throws ContributionReadException {

+        

+        if (packageSourceURL == null) {

+            throw new IllegalArgumentException("Invalid null package source URL.");

+        }

+        Bundle bundle = OSGiBundleActivator.findBundle(packageSourceURL);

+        

+        if (bundle == null) {

+            throw new IllegalArgumentException("Could not find OSGi bundle " + packageSourceURL);

+        }

+

+        List<String> artifacts = new ArrayList<String>();

+

+        try {

+            Enumeration<?> entries = bundle.findEntries("/", "*", true);

+            while (entries.hasMoreElements()) {

+                URL entry = (URL)entries.nextElement();

+                String entryName = entry.getPath();

+                if (entryName.startsWith("/"))

+                    entryName = entryName.substring(1);

+                artifacts.add(entryName);

+                

+                if (entryName.endsWith(".jar")) {

+

+                    URL jarResource = bundle.getResource(entryName);

+                    artifacts.addAll(getJarArtifacts(jarResource, jarResource.openStream()));

+                }

+            

+            }

+        } catch (Exception e) {

+            throw new RuntimeException(e);

+        }

+

+        return artifacts;

+    }

+}

diff --git a/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleProcessor.java b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleProcessor.java
new file mode 100644
index 0000000000..0b0d49de3e
--- /dev/null
+++ b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleProcessor.java
@@ -0,0 +1,75 @@
+/*
+ * 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.osgi.impl;
+
+import java.util.List;
+
+import org.apache.tuscany.sca.contribution.Artifact;
+import org.apache.tuscany.sca.contribution.Contribution;
+import org.apache.tuscany.sca.contribution.osgi.BundleReference;
+import org.osgi.framework.Bundle;
+
+/**
+ * OSGi bundle processor
+ *
+ * @version $Rev$ $Date$
+ */
+public class OSGiBundleProcessor {
+
+    //    private boolean initializedOSGi;
+    //    private OSGiRuntime osgiRuntime;
+
+    public OSGiBundleProcessor() {
+    }
+
+    public Object installContributionBundle(Contribution contribution) {
+
+        Object bundle = null;
+        try {
+            bundle = OSGiBundleActivator.installBundle(contribution.getLocation());
+        } catch (Exception e) {
+            // If OSGi cannot process the jar, treat the bundle as a plain jar file.
+        }
+        return bundle;
+    }
+
+    public BundleReference installNestedBundle(Contribution contribution,
+                                               String bundleSymbolicName,
+                                               String bundleVersion) {
+
+        BundleReference bundleReference = null;
+
+        List<Artifact> artifacts = contribution.getArtifacts();
+        for (Artifact a : artifacts) {
+            if (a.getURI().endsWith(".jar")) {
+                try {
+                    Bundle bundle = OSGiBundleActivator.installBundle(a.getLocation());
+                    if (bundle != null) {
+                        bundleReference = new BundleReference(bundle);
+                        break;
+                    }
+                } catch (Exception e) {
+                    // If OSGi cannot process the jar, treat the bundle as a plain jar file.
+                }
+            }
+        }
+        return bundleReference;
+    }
+}
diff --git a/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleReferenceModelResolver.java b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleReferenceModelResolver.java
new file mode 100644
index 0000000000..e63bbc495f
--- /dev/null
+++ b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiBundleReferenceModelResolver.java
@@ -0,0 +1,115 @@
+/*
+ * 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.osgi.impl;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.tuscany.sca.contribution.Contribution;
+import org.apache.tuscany.sca.contribution.Import;
+import org.apache.tuscany.sca.contribution.osgi.BundleReference;
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.core.FactoryExtensionPoint;
+import org.osgi.framework.Bundle;
+
+/**
+ * A Model Resolver for BundleReferences.
+ *
+ * @version $Rev$ $Date$
+ */
+public class OSGiBundleReferenceModelResolver implements ModelResolver {
+    private Contribution contribution;
+    private Map<BundleReference, BundleReference> refs = new HashMap<BundleReference, BundleReference>();
+
+    private OSGiBundleProcessor bundleProcessor;
+
+    public OSGiBundleReferenceModelResolver(Contribution contribution, FactoryExtensionPoint modelFactories) {
+        this.contribution = contribution;
+        this.bundleProcessor = new OSGiBundleProcessor();
+    }
+
+    public void addModel(Object resolved) {
+        BundleReference bundleRef = (BundleReference)resolved;
+        refs.put(bundleRef, bundleRef);
+    }
+
+    public Object removeModel(Object resolved) {
+        return refs.remove(resolved);
+    }
+
+    /**
+     * Handle artifact resolution when the specific class reference is imported from another contribution
+     * @param unresolved
+     * @return
+     */
+    private BundleReference resolveImportedModel(BundleReference unresolved) {
+        BundleReference resolved = unresolved;
+
+        if (this.contribution != null) {
+            for (Import import_ : this.contribution.getImports()) {
+
+                resolved = import_.getModelResolver().resolveModel(BundleReference.class, unresolved);
+                if (resolved != unresolved)
+                    break;
+            }
+
+        }
+        return resolved;
+    }
+
+    public <T> T resolveModel(Class<T> modelClass, T unresolved) {
+        Object resolved = refs.get(unresolved);
+
+        if (resolved != null) {
+            return modelClass.cast(resolved);
+        }
+
+        if (OSGiBundleActivator.getBundleContext() == null)
+            return unresolved;
+
+        //Load a class on demand
+        Bundle bundle = null;
+        String bundleName = ((BundleReference)unresolved).getSymbolicName();
+        String bundleVersion = ((BundleReference)unresolved).getVersion();
+
+        bundle = OSGiBundleActivator.findBundle(bundleName, bundleVersion);
+        BundleReference bundleReference;
+
+        if (bundle == null) {
+            bundleReference = bundleProcessor.installNestedBundle(contribution, bundleName, bundleVersion);
+        } else {
+            bundleReference = new BundleReference(bundle);
+        }
+
+        if (bundleReference != null) {
+            //if we load the class            
+
+            refs.put(((BundleReference)unresolved), bundleReference);
+
+            // Return the resolved BundleReference
+            return modelClass.cast(bundleReference);
+        } else {
+            //delegate resolution of the class
+            resolved = this.resolveImportedModel((BundleReference)unresolved);
+            return modelClass.cast(resolved);
+        }
+
+    }
+}
diff --git a/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiClassReferenceModelResolver.java b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiClassReferenceModelResolver.java
new file mode 100644
index 0000000000..15b77490b8
--- /dev/null
+++ b/branches/sca-java-2.0-M2/modules/contribution-osgi/src/main/java/org/apache/tuscany/sca/contribution/osgi/impl/OSGiClassReferenceModelResolver.java
@@ -0,0 +1,132 @@
+/*
+ * 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.osgi.impl;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.tuscany.sca.contribution.Contribution;
+import org.apache.tuscany.sca.contribution.Import;
+import org.apache.tuscany.sca.contribution.resolver.ClassReference;
+import org.apache.tuscany.sca.contribution.resolver.ModelResolver;
+import org.apache.tuscany.sca.core.FactoryExtensionPoint;
+import org.osgi.framework.Bundle;
+
+/**
+ * A Model Resolver for ClassReferences.
+ *
+ * @version $Rev$ $Date$
+ */
+public class OSGiClassReferenceModelResolver implements ModelResolver {
+    private Contribution contribution;
+    private Map<String, ClassReference> map = new HashMap<String, ClassReference>();
+    private Bundle bundle;
+    private boolean initialized;
+    private boolean useOSGi;
+
+    public OSGiClassReferenceModelResolver(Contribution contribution, FactoryExtensionPoint modelFactories) {
+        this.contribution = contribution;
+    }
+
+    public void addModel(Object resolved) {
+        ClassReference clazz = (ClassReference)resolved;
+        map.put(clazz.getClassName(), clazz);
+    }
+
+    public Object removeModel(Object resolved) {
+        return map.remove(((ClassReference)resolved).getClassName());
+    }
+
+    /**
+     * Handle artifact resolution when the specific class reference is imported from another contribution
+     * @param unresolved
+     * @return
+     */
+    private ClassReference resolveImportedModel(ClassReference unresolved) {
+        ClassReference resolved = unresolved;
+
+        if (this.contribution != null) {
+            for (Import import_ : this.contribution.getImports()) {
+
+                if (resolved == unresolved && bundle != null) {
+                    resolved = import_.getModelResolver().resolveModel(ClassReference.class, unresolved);
+                    if (resolved != unresolved)
+                        break;
+                }
+            }
+
+        }
+        return resolved;
+    }
+
+    public <T> T resolveModel(Class<T> modelClass, T unresolved) {
+        Object resolved = map.get(unresolved);
+
+        if (resolved != null) {
+            return modelClass.cast(resolved);
+        }
+        initialize();
+        if (!useOSGi)
+            return unresolved;
+
+        //Load a class on demand
+        Class clazz = null;
+        if (bundle != null) {
+            try {
+                clazz = bundle.loadClass(((ClassReference)unresolved).getClassName());
+            } catch (Exception e) {
+                // we will later try to delegate to imported model resolvers
+            }
+        }
+
+        if (clazz != null) {
+            //if we load the class            
+            // Store a new ClassReference wrapping the loaded class
+            ClassReference classReference = new ClassReference(clazz);
+            map.put(getPackageName(classReference), classReference);
+
+            // Return the resolved ClassReference
+            return modelClass.cast(classReference);
+        } else {
+            //delegate resolution of the class
+            resolved = this.resolveImportedModel((ClassReference)unresolved);
+            return modelClass.cast(resolved);
+        }
+
+    }
+
+    /***************
+     * Helper methods
+     ***************/
+
+    private String getPackageName(ClassReference clazz) {
+        int pos = clazz.getClassName().lastIndexOf(".");
+        return clazz.getClassName().substring(0, pos - 1);
+    }
+
+    private void initialize() {
+        try {
+            bundle = OSGiBundleActivator.findBundle(contribution.getLocation());
+            useOSGi = bundle != null;
+        } catch (Throwable e) {
+            // Ignore errors, default to ClassReferenceModelResolver
+        }
+    }
+}