1 files changed, 115 insertions, 0 deletions
diff --git a/sca-java-2.x/tags/2.0.1-RC1/modules/core-spi/src/main/java/org/apache/tuscany/sca/context/DefaultContextFactoryExtensionPoint.java b/sca-java-2.x/tags/2.0.1-RC1/modules/core-spi/src/main/java/org/apache/tuscany/sca/context/DefaultContextFactoryExtensionPoint.java
new file mode 100644
index 0000000000..50882c9498
--- /dev/null
+++ b/sca-java-2.x/tags/2.0.1-RC1/modules/core-spi/src/main/java/org/apache/tuscany/sca/context/DefaultContextFactoryExtensionPoint.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.context;
+
+import java.lang.reflect.Constructor;
+import java.util.HashMap;
+
+import org.apache.tuscany.sca.core.ExtensionPointRegistry;
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+
+/**
+ * Default implementation of a model factory extension point.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultContextFactoryExtensionPoint implements ContextFactoryExtensionPoint {
+
+    /**
+     * The Map of Factories that have been registered.
+     */
+    private HashMap<Class<?>, Object> factories = new HashMap<Class<?>, Object>();
+
+    private ExtensionPointRegistry registry;
+
+    public DefaultContextFactoryExtensionPoint(ExtensionPointRegistry registry) {
+        this.registry = registry;
+    }
+
+    /**
+     * Add a model factory extension.
+     *
+     * @param factory The factory to add.
+     * @throws IllegalArgumentException if factory is null
+     */
+    public void addFactory(Object factory) throws IllegalArgumentException {
+        if (factory == null) {
+            throw new IllegalArgumentException("Cannot add null as a factory");
+        }
+
+        Class<?>[] interfaces = factory.getClass().getInterfaces();
+        for (int i = 0; i<interfaces.length; i++) {
+            factories.put(interfaces[i], factory);
+        }
+    }
+
+    /**
+     * Remove a model factory extension.
+     *
+     * @param factory The factory to remove
+     * @throws IllegalArgumentException if factory is null
+     */
+    public void removeFactory(Object factory) throws IllegalArgumentException {
+        if (factory == null) {
+            throw new IllegalArgumentException("Cannot remove null as a factory");
+        }
+
+        Class<?>[] interfaces = factory.getClass().getInterfaces();
+        for (int i = 0; i<interfaces.length; i++) {
+            factories.remove(interfaces[i]);
+        }
+    }
+
+    /**
+     * Get a factory implementing the given interface.
+     *
+     * @param factoryInterface The lookup key (factory interface)
+     * @return The factory
+     */
+    public <T> T getFactory(Class<T> factoryInterface) throws IllegalArgumentException {
+        if (factoryInterface == null) {
+            throw new IllegalArgumentException("Cannot get null as a factory");
+        }
+
+        Object factory = factories.get(factoryInterface);
+        if (factory == null) {
+
+            // Dynamically load a factory class declared under META-INF/services
+            try {
+                ServiceDeclaration factoryDeclaration = registry.getServiceDiscovery().getServiceDeclaration(factoryInterface.getName());
+                if (factoryDeclaration != null) {
+                    Class<?> factoryClass = factoryDeclaration.loadClass();
+            
+                    // Default empty constructor
+                    Constructor<?> constructor = factoryClass.getConstructor(ExtensionPointRegistry.class);
+                    factory = constructor.newInstance(registry);
+            
+                    // Cache the loaded factory
+                    addFactory(factory);
+                }
+            } catch (Exception e) {
+                throw new IllegalArgumentException(e);
+            }
+
+        }
+
+        return factoryInterface.cast(factory);
+    }
+}