1 files changed, 261 insertions, 0 deletions
diff --git a/sca-java-2.x/tags/2.0.1-RC1/modules/databinding/src/main/java/org/apache/tuscany/sca/databinding/DefaultDataBindingExtensionPoint.java b/sca-java-2.x/tags/2.0.1-RC1/modules/databinding/src/main/java/org/apache/tuscany/sca/databinding/DefaultDataBindingExtensionPoint.java
new file mode 100644
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--- /dev/null
+++ b/sca-java-2.x/tags/2.0.1-RC1/modules/databinding/src/main/java/org/apache/tuscany/sca/databinding/DefaultDataBindingExtensionPoint.java
@@ -0,0 +1,261 @@
+/*
+ * 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.databinding;
+
+import java.io.IOException;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.GenericArrayType;
+import java.lang.reflect.Type;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import org.apache.tuscany.sca.core.ExtensionPointRegistry;
+import org.apache.tuscany.sca.databinding.javabeans.JavaBeansDataBinding;
+import org.apache.tuscany.sca.databinding.javabeans.JavaExceptionDataBinding;
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.interfacedef.DataType;
+import org.apache.tuscany.sca.interfacedef.Operation;
+import org.apache.tuscany.sca.interfacedef.impl.DataTypeImpl;
+import org.apache.tuscany.sca.interfacedef.util.XMLType;
+
+/**
+ * The default implementation of a data binding extension point.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultDataBindingExtensionPoint implements DataBindingExtensionPoint {
+    private ExtensionPointRegistry registry;
+    private final Map<String, DataBinding> bindings = new HashMap<String, DataBinding>();
+    private final List<DataBinding> databindings = new ArrayList<DataBinding>();
+    private static final Logger logger = Logger.getLogger(DefaultDataBindingExtensionPoint.class.getName());
+    private boolean loadedDataBindings;
+
+//    public DefaultDataBindingExtensionPoint() {
+//    }
+
+    public DefaultDataBindingExtensionPoint(ExtensionPointRegistry registry) {
+        this.registry = registry;
+    }
+
+    public DataBinding getDataBinding(String id) {
+        if (id == null) {
+            return null;
+        }
+        loadDataBindings();
+        DataBinding dataBinding = bindings.get(id.toLowerCase());
+        if (dataBinding == null) {
+            loadDataBindings();
+            dataBinding = bindings.get(id.toLowerCase());
+        }
+        return dataBinding;
+    }
+
+    public void addDataBinding(DataBinding dataBinding) {
+        if (logger.isLoggable(Level.FINE)) {
+            String className = dataBinding.getClass().getName();
+            boolean lazy = false;
+            if (dataBinding instanceof LazyDataBinding) {
+                className = ((LazyDataBinding)dataBinding).dataBindingDeclaration.getClassName();
+                lazy = true;
+            }
+            logger.fine("Adding databinding: " + className + ";name=" + dataBinding.getName() + ",lazy=" + lazy);
+        }
+        databindings.add(dataBinding);
+        bindings.put(dataBinding.getName().toLowerCase(), dataBinding);
+
+    }
+
+    public DataBinding removeDataBinding(String id) {
+        if (id == null) {
+            return null;
+        }
+        DataBinding dataBinding = bindings.remove(id.toLowerCase());
+        if (dataBinding != null) {
+            databindings.remove(dataBinding);
+        }
+        return dataBinding;
+    }
+
+    /**
+     * Dynamically load data bindings declared under META-INF/services
+     */
+    private synchronized void loadDataBindings() {
+        if (loadedDataBindings)
+            return;
+
+        // Get the databinding service declarations
+        Collection<ServiceDeclaration> dataBindingDeclarations;
+        try {
+            dataBindingDeclarations = registry.getServiceDiscovery().getServiceDeclarations(DataBinding.class.getName());
+        } catch (IOException e) {
+            throw new IllegalStateException(e);
+        }
+
+        // Load data bindings
+        for (ServiceDeclaration dataBindingDeclaration : dataBindingDeclarations) {
+            Map<String, String> attributes = dataBindingDeclaration.getAttributes();
+            String name = attributes.get("name");
+
+            // Create a data binding wrapper and register it
+            DataBinding dataBinding = new LazyDataBinding(name, dataBindingDeclaration);
+            addDataBinding(dataBinding);
+        }
+
+        loadedDataBindings = true;
+    }
+
+    /**
+     * A data binding facade allowing data bindings to be lazily loaded and
+     * initialized.
+     */
+    private class LazyDataBinding implements DataBinding {
+
+        private String name;
+        private ServiceDeclaration dataBindingDeclaration;
+        private DataBinding dataBinding;
+
+        private LazyDataBinding(String type, ServiceDeclaration dataBindingDeclaration) {
+            this.name = type;
+            this.dataBindingDeclaration = dataBindingDeclaration;
+        }
+
+        /**
+         * Load and instantiate the data binding class.
+         *
+         * @return The data binding.
+         */
+        @SuppressWarnings("unchecked")
+        private DataBinding getDataBinding() {
+            if (dataBinding == null) {
+                try {
+                    Class<DataBinding> dataBindingClass = (Class<DataBinding>)dataBindingDeclaration.loadClass();
+                    try {
+                        Constructor<DataBinding> constructor = dataBindingClass.getConstructor();
+                        dataBinding = constructor.newInstance();
+                    } catch (NoSuchMethodException e) {
+                        Constructor<DataBinding> constructor =
+                            dataBindingClass.getConstructor(ExtensionPointRegistry.class);
+                        dataBinding = constructor.newInstance(DefaultDataBindingExtensionPoint.this.registry);
+                    }
+                } catch (Exception e) {
+                    throw new IllegalStateException(e);
+                }
+            }
+            return dataBinding;
+        }
+
+        public Object copy(Object object, DataType sourceDataType, DataType targetDataType, Operation sourceOperation, Operation targetOperation) {
+            return getDataBinding().copy(object, sourceDataType, targetDataType, sourceOperation, targetOperation);
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public XMLTypeHelper getXMLTypeHelper() {
+            return getDataBinding().getXMLTypeHelper();
+        }
+
+        public WrapperHandler getWrapperHandler() {
+            return getDataBinding().getWrapperHandler();
+        }
+
+        public boolean introspect(DataType dataType, Operation operation) {
+            return getDataBinding().introspect(dataType, operation);
+        }
+
+        public DataType introspect(Object value, Operation operation) {
+            return getDataBinding().introspect(value, operation);
+        }
+    }
+
+    //FIXME The following methods should not be on the extension point
+    // they should be on a separate class
+    public boolean introspectType(DataType dataType, Operation operation) {
+        loadDataBindings();
+        for (DataBinding binding : databindings) {
+            // don't introspect for JavaBeansDatabinding as all javatypes will
+            // anyways match to its basetype
+            // which is java.lang.Object. Default to this only if no databinding
+            // results
+            if (!binding.getName().equals(JavaBeansDataBinding.NAME)) {
+                if (binding.introspect(dataType, operation)) {
+                    return true;
+                }
+            }
+        }
+        // FIXME: Should we honor the databinding from operation/interface
+        // level?
+        Class<?> physical = dataType.getPhysical();
+        if (physical == Object.class) {
+            dataType.setDataBinding(JavaBeansDataBinding.NAME);
+            return false;
+        }
+        if (dataType.getPhysical().isArray()) {
+            introspectArray(dataType, operation);
+            return true;
+        } else if (Throwable.class.isAssignableFrom(physical)) {
+            dataType.setDataBinding(JavaExceptionDataBinding.NAME);
+            return true;
+        } else {
+            dataType.setDataBinding(JavaBeansDataBinding.NAME);
+            return false;
+        }
+    }
+
+    private boolean introspectArray(DataType dataType, Operation operation) {
+        Class<?> physical = dataType.getPhysical();
+        if (!physical.isArray() || physical == byte[].class) {
+            return false;
+        }
+        Class<?> componentType = physical.getComponentType();
+        Type genericComponentType = componentType;
+        if(dataType.getGenericType() instanceof GenericArrayType) {
+            genericComponentType = ((GenericArrayType) dataType.getGenericType()).getGenericComponentType();
+        }
+        DataType logical = new DataTypeImpl(dataType.getDataBinding(), componentType, genericComponentType, dataType.getLogical());
+        introspectType(logical, operation);
+        dataType.setDataBinding("java:array");
+        dataType.setLogical(logical);
+        return true;
+    }
+
+    public DataType introspectType(Object value, Operation operation) {
+        loadDataBindings();
+        DataType dataType = null;
+        for (DataBinding binding : databindings) {
+            // don't introspect for JavaBeansDatabinding as all javatypes will
+            // anyways match to its basetype
+            // which is java.lang.Object. Default to this only if no databinding
+            // results
+            if (!binding.getName().equals(JavaBeansDataBinding.NAME)) {
+                dataType = binding.introspect(value, operation);
+            }
+            if (dataType != null) {
+                return dataType;
+            }
+        }
+        return new DataTypeImpl<XMLType>(JavaBeansDataBinding.NAME, value.getClass(), XMLType.UNKNOWN);
+    }
+}