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-rw-r--r--tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java226
-rw-r--r--tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultFactoryExtensionPoint.java174
-rw-r--r--tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java112
-rw-r--r--tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java197
-rw-r--r--tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.java61
-rw-r--r--tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/FactoryExtensionPoint.java54
-rw-r--r--tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivator.java60
-rw-r--r--tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivatorExtensionPoint.java53
-rw-r--r--tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.java64
9 files changed, 1001 insertions, 0 deletions
diff --git a/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java
new file mode 100644
index 0000000000..3ea587c5f2
--- /dev/null
+++ b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java
@@ -0,0 +1,226 @@
+/*
+ * 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.core;
+
+import java.io.IOException;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Modifier;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.IdentityHashMap;
+import java.util.Map;
+import java.util.Set;
+
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+
+/**
+ * Default implementation of a registry to hold all the Tuscany core extension
+ * points. As the point of contact for all extension artifacts this registry
+ * allows loaded extensions to find all other parts of the system and register
+ * themselves appropriately.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultExtensionPointRegistry implements ExtensionPointRegistry {
+ private Map<Class<?>, Object> extensionPoints = new HashMap<Class<?>, Object>();
+
+ /**
+ * Constructs a new registry.
+ */
+ public DefaultExtensionPointRegistry() {
+ }
+
+ /**
+ * Add an extension point to the registry. This default implementation
+ * stores extensions against the interfaces that they implement.
+ *
+ * @param extensionPoint The instance of the extension point
+ *
+ * @throws IllegalArgumentException if extensionPoint is null
+ */
+ public synchronized void addExtensionPoint(Object extensionPoint) {
+ addExtensionPoint(extensionPoint, null);
+ }
+
+ public synchronized void addExtensionPoint(Object extensionPoint, ServiceDeclaration declaration) {
+ if (extensionPoint == null) {
+ throw new IllegalArgumentException("Cannot register null as an ExtensionPoint");
+ }
+ if (extensionPoint instanceof ModuleActivator) {
+ ((ModuleActivator)extensionPoint).start(this);
+ }
+ Set<Class<?>> interfaces = getAllInterfaces(extensionPoint.getClass());
+ for (Class<?> i : interfaces) {
+ registerExtensionPoint(i, extensionPoint, declaration);
+ }
+ }
+
+ protected void registerExtensionPoint(Class<?> i, Object extensionPoint, ServiceDeclaration declaration) {
+ extensionPoints.put(i, extensionPoint);
+ }
+
+ private Constructor<?> getConstructor(Constructor<?>[] constructors, Class<?>[] paramTypes) {
+ for (Constructor<?> c : constructors) {
+ Class<?>[] types = c.getParameterTypes();
+ if (c.getParameterTypes().length == paramTypes.length) {
+ boolean found = true;
+ for (int i = 0; i < types.length; i++) {
+ if (types[i] != paramTypes[i]) {
+ found = false;
+ break;
+ }
+ }
+ if (found) {
+ return c;
+ }
+ }
+ }
+ return null;
+ }
+
+ /**
+ * Get the extension point by the interface that it implements
+ *
+ * @param extensionPointType The lookup key (extension point interface)
+ * @return The instance of the extension point
+ *
+ * @throws IllegalArgumentException if extensionPointType is null
+ */
+ public synchronized <T> T getExtensionPoint(Class<T> extensionPointType) {
+ if (extensionPointType == null) {
+ throw new IllegalArgumentException("Cannot lookup ExtensionPoint of type null");
+ }
+
+ Object extensionPoint = findExtensionPoint(extensionPointType);
+ if (extensionPoint == null) {
+
+ // Dynamically load an extension point class declared under META-INF/services
+ try {
+ ServiceDeclaration extensionPointDeclaration =
+ ServiceDiscovery.getInstance().getServiceDeclaration(extensionPointType.getName());
+ if (extensionPointDeclaration != null) {
+ Class<?> extensionPointClass = extensionPointDeclaration.loadClass();
+
+ // Construct the extension point
+ Constructor<?>[] constructors = extensionPointClass.getConstructors();
+ Constructor<?> constructor =
+ getConstructor(constructors, new Class<?>[] {ExtensionPointRegistry.class});
+ if (constructor != null) {
+ extensionPoint = constructor.newInstance(this);
+ } else {
+ constructor = getConstructor(constructors, new Class<?>[] {});
+ if (constructor != null) {
+ extensionPoint = constructor.newInstance();
+ } else {
+ throw new IllegalArgumentException(
+ "No valid constructor is found for " + extensionPointClass);
+ }
+ }
+
+ // Cache the loaded extension point
+ addExtensionPoint(extensionPoint, extensionPointDeclaration);
+ }
+ } catch (InvocationTargetException e) {
+ throw new IllegalArgumentException(e);
+ } catch (IOException e) {
+ throw new IllegalArgumentException(e);
+ } catch (ClassNotFoundException e) {
+ throw new IllegalArgumentException(e);
+ } catch (InstantiationException e) {
+ throw new IllegalArgumentException(e);
+ } catch (IllegalAccessException e) {
+ throw new IllegalArgumentException(e);
+ }
+ }
+ return extensionPointType.cast(extensionPoint);
+ }
+
+ protected <T> Object findExtensionPoint(Class<T> extensionPointType) {
+ return extensionPoints.get(extensionPointType);
+ }
+
+ /**
+ * Remove an extension point based on the interface that it implements
+ *
+ * @param extensionPoint The extension point to remove
+ *
+ * @throws IllegalArgumentException if extensionPoint is null
+ */
+ public synchronized void removeExtensionPoint(Object extensionPoint) {
+ if (extensionPoint == null) {
+ throw new IllegalArgumentException("Cannot remove null as an ExtensionPoint");
+ }
+
+ if (extensionPoint instanceof ModuleActivator) {
+ ((ModuleActivator)extensionPoint).stop(this);
+ }
+
+ Set<Class<?>> interfaces = getAllInterfaces(extensionPoint.getClass());
+ for (Class<?> i : interfaces) {
+ unregisterExtensionPoint(i);
+ }
+ }
+
+ protected void unregisterExtensionPoint(Class<?> i) {
+ extensionPoints.remove(i);
+ }
+
+ /**
+ * Returns the set of interfaces implemented by the given class and its
+ * ancestors or a blank set if none
+ */
+ private static Set<Class<?>> getAllInterfaces(Class<?> clazz) {
+ Set<Class<?>> implemented = new HashSet<Class<?>>();
+ getAllInterfaces(clazz, implemented);
+ return implemented;
+ }
+
+ private static void getAllInterfaces(Class<?> clazz, Set<Class<?>> implemented) {
+ Class<?>[] interfaces = clazz.getInterfaces();
+ for (Class<?> interfaze : interfaces) {
+ if (Modifier.isPublic(interfaze.getModifiers())) {
+ implemented.add(interfaze);
+ }
+ }
+ Class<?> superClass = clazz.getSuperclass();
+ // Object has no superclass so check for null
+ if (superClass != null && !superClass.equals(Object.class)) {
+ getAllInterfaces(superClass, implemented);
+ }
+ }
+
+ public void destroy() {
+ // Get a unique map as an extension point may exist in the map by different keys
+ Map<ModuleActivator, ModuleActivator> map = new IdentityHashMap<ModuleActivator, ModuleActivator>();
+ for (Object extp : extensionPoints.values()) {
+ if (extp instanceof ModuleActivator) {
+ ModuleActivator activator = (ModuleActivator)extp;
+ map.put(activator, activator);
+ }
+ }
+ for (ModuleActivator activator : map.values()) {
+ activator.stop(this);
+ }
+ extensionPoints.clear();
+ }
+
+}
diff --git a/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultFactoryExtensionPoint.java b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultFactoryExtensionPoint.java
new file mode 100644
index 0000000000..54d0d118bb
--- /dev/null
+++ b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultFactoryExtensionPoint.java
@@ -0,0 +1,174 @@
+/*
+ * 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.core;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+import java.security.AccessController;
+import java.security.PrivilegedAction;
+import java.util.HashMap;
+
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+
+
+
+/**
+ * Default implementation of a model factory extension point.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultFactoryExtensionPoint implements FactoryExtensionPoint {
+ private ExtensionPointRegistry extensionPointRegistry;
+ private HashMap<Class<?>, Object> factories = new HashMap<Class<?>, Object>();
+
+ /**
+ * Constructs a new DefaultModelFactoryExtensionPoint.
+ */
+ public DefaultFactoryExtensionPoint(ExtensionPointRegistry extensionPointRegistry) {
+ this.extensionPointRegistry = extensionPointRegistry;
+ }
+
+ /**
+ * Add a model factory extension.
+ *
+ * @param factory The factory to add
+ */
+ public void addFactory(Object factory) {
+ Class<?>[] interfaces = factory.getClass().getInterfaces();
+ if (interfaces.length == 0) {
+ Class<?> sc = factory.getClass().getSuperclass();
+ if (sc != Object.class) {
+ factories.put(sc, factory);
+ }
+ } else {
+ for (int i = 0; i<interfaces.length; i++) {
+ factories.put(interfaces[i], factory);
+ }
+ }
+ }
+
+ /**
+ * Remove a model factory.
+ *
+ * @param factory The factory to remove
+ */
+ public void removeFactory(Object factory) {
+ Class<?>[] interfaces = factory.getClass().getInterfaces();
+ if (interfaces.length == 0) {
+ Class<?> sc = factory.getClass().getSuperclass();
+ if (sc != Object.class) {
+ factories.remove(sc);
+ }
+ } else {
+ for (int i = 0; i<interfaces.length; i++) {
+ factories.remove(interfaces[i]);
+ }
+ }
+ }
+
+ private ClassLoader setContextClassLoader(final ClassLoader classLoader) {
+ return AccessController.doPrivileged(new PrivilegedAction<ClassLoader>() {
+ public ClassLoader run() {
+ ClassLoader tccl = Thread.currentThread().getContextClassLoader();
+ if (classLoader != null) {
+ Thread.currentThread().setContextClassLoader(classLoader);
+ }
+ return tccl;
+ }
+ });
+ }
+
+ /**
+ * Get a factory implementing the given interface.
+ * @param factoryInterface The lookup key (factory interface)
+ * @return The factory
+ */
+ public <T> T getFactory(Class<T> factoryInterface) {
+ Object factory = factories.get(factoryInterface);
+ if (factory == null) {
+
+ // Dynamically load a factory class declared under META-INF/services
+ try {
+ ServiceDeclaration factoryDeclaration =
+ ServiceDiscovery.getInstance().getServiceDeclaration(factoryInterface.getName());
+ if (factoryDeclaration != null) {
+ Class<?> factoryClass = factoryDeclaration.loadClass();
+ try {
+
+ // Default empty constructor
+ Constructor<?> constructor = factoryClass.getConstructor();
+ factory = constructor.newInstance();
+ } catch (NoSuchMethodException e) {
+ try {
+
+ // Constructor taking the model factory extension point
+ Constructor<?> constructor = factoryClass.getConstructor(FactoryExtensionPoint.class);
+ factory = constructor.newInstance(this);
+ } catch (NoSuchMethodException e1) {
+
+ // Constructor taking the extension point registry
+ Constructor<?> constructor = factoryClass.getConstructor(ExtensionPointRegistry.class);
+ factory = constructor.newInstance(extensionPointRegistry);
+ }
+ }
+
+ // Cache the loaded factory
+ factories.put(factoryInterface, factory);
+
+ return factoryInterface.cast(factory);
+
+ } else {
+
+ // If the input interface is an abstract class
+ if (!factoryInterface.isInterface() && Modifier.isAbstract(factoryInterface.getModifiers())) {
+ Method newInstanceMethod = factoryInterface.getDeclaredMethod("newInstance");
+ ClassLoader tccl = setContextClassLoader(factoryInterface.getClassLoader());
+ try {
+
+ // Create a new instance
+ factory = newInstanceMethod.invoke(null);
+
+ // Cache the factory
+ factories.put(factoryInterface, factory);
+
+ return factoryInterface.cast(factory);
+ } catch (Exception e) {
+ // Sorry no factory found
+ return null;
+ } finally {
+ setContextClassLoader(tccl);
+ }
+ } else {
+
+ // Sorry no factory found
+ return null;
+ }
+ }
+ } catch (Exception e) {
+ throw new IllegalArgumentException(e);
+ }
+ } else {
+ return factoryInterface.cast(factory);
+ }
+ }
+
+}
diff --git a/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java
new file mode 100644
index 0000000000..f9228efd71
--- /dev/null
+++ b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java
@@ -0,0 +1,112 @@
+/*
+ * 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.core;
+
+import java.io.IOException;
+import java.lang.reflect.Constructor;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.List;
+import java.util.Map;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+
+/**
+ * Default implementation of an extension point to hold Tuscany module activators.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultModuleActivatorExtensionPoint implements ModuleActivatorExtensionPoint {
+ private final static Logger logger = Logger.getLogger(DefaultModuleActivatorExtensionPoint.class.getName());
+ private List<ModuleActivator> activators = new ArrayList<ModuleActivator>();
+ private boolean loadedActivators;
+
+ /**
+ * Constructs a new extension point.
+ */
+ public DefaultModuleActivatorExtensionPoint() {
+ }
+
+ public void addModuleActivator(ModuleActivator activator) {
+ activators.add(activator);
+ }
+
+ public List<ModuleActivator> getModuleActivators() {
+ loadModuleActivators();
+ return activators;
+ }
+
+ public void removeModuleActivator(Object activator) {
+ activators.remove(activator);
+ }
+
+ /**
+ * Dynamically load module activators declared under META-INF/services
+ */
+ private synchronized void loadModuleActivators() {
+ if (loadedActivators)
+ return;
+
+ // Get the activator service declarations
+ Collection<ServiceDeclaration> activatorDeclarations;
+ try {
+ // Load the module activators by ranking
+ activatorDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations(ModuleActivator.class.getName(), true);
+ } catch (IOException e) {
+ throw new IllegalStateException(e);
+ }
+
+ // Load and instantiate module activators
+ for (ServiceDeclaration activatorDeclaration : activatorDeclarations) {
+ if (logger.isLoggable(Level.FINE)) {
+ logger.fine("Loading " + activatorDeclaration.getClassName());
+ }
+ ModuleActivator activator = null;
+ try {
+ Class<ModuleActivator> activatorClass = (Class<ModuleActivator>)activatorDeclaration.loadClass();
+ Constructor<ModuleActivator> constructor = null;
+ try {
+ constructor = activatorClass.getConstructor();
+ activator = constructor.newInstance();
+ } catch (NoSuchMethodException e) {
+ // Try the one that takes a Map<String, String>
+ constructor = activatorClass.getConstructor(Map.class);
+ activator = constructor.newInstance(activatorDeclaration.getAttributes());
+ }
+ } catch (Throwable e) {
+ String optional = activatorDeclaration.getAttributes().get("optional");
+ if ("true".equalsIgnoreCase(optional)) {
+ // If the optional flag is true, just log the error
+ logger.log(Level.SEVERE, e.getMessage(), e);
+ continue;
+ } else {
+ throw new IllegalArgumentException(e);
+ }
+ }
+ addModuleActivator(activator);
+ }
+
+ loadedActivators = true;
+ }
+
+}
diff --git a/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java
new file mode 100644
index 0000000000..c7ff4e1858
--- /dev/null
+++ b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java
@@ -0,0 +1,197 @@
+/*
+ * 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.core;
+
+import java.io.IOException;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Modifier;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.apache.tuscany.sca.extensibility.ServiceDeclaration;
+import org.apache.tuscany.sca.extensibility.ServiceDiscovery;
+
+/**
+ * Default implementation of an extension point to hold Tuscany utility utilities.
+ *
+ * @version $Rev$ $Date$
+ */
+public class DefaultUtilityExtensionPoint implements UtilityExtensionPoint {
+ private Map<Class<?>, Object> utilities = new ConcurrentHashMap<Class<?>, Object>();
+
+ private ExtensionPointRegistry extensionPoints;
+
+ /**
+ * Constructs a new extension point.
+ */
+ public DefaultUtilityExtensionPoint(ExtensionPointRegistry extensionPoints) {
+ this.extensionPoints = extensionPoints;
+ }
+
+ /**
+ * Add a utility to the extension point. This default implementation
+ * stores utilities against the interfaces that they implement.
+ *
+ * @param utility The instance of the utility
+ *
+ * @throws IllegalArgumentException if utility is null
+ */
+ public void addUtility(Object utility) {
+ if (utility == null) {
+ throw new IllegalArgumentException("Cannot register null as a Service");
+ }
+
+ Set<Class<?>> interfaces = getAllInterfaces(utility.getClass());
+ for (Class<?> i : interfaces) {
+ utilities.put(i, utility);
+ }
+ }
+
+ private Constructor<?> getConstructor(Constructor<?>[] constructors, Class<?>... paramTypes) {
+ for (Constructor<?> c : constructors) {
+ Class<?>[] types = c.getParameterTypes();
+ if (c.getParameterTypes().length == paramTypes.length) {
+ boolean found = true;
+ for (int i = 0; i < types.length; i++) {
+ if (types[i] != paramTypes[i]) {
+ found = false;
+ break;
+ }
+ }
+ if (found) {
+ return c;
+ }
+ }
+ }
+ return null;
+ }
+
+ /**
+ * Get the utility by the interface that it implements
+ *
+ * @param utilityType The lookup key (utility interface)
+ * @return The instance of the utility
+ *
+ * @throws IllegalArgumentException if utilityType is null
+ */
+ public <T> T getUtility(Class<T> utilityType) {
+ return getUtility(utilityType, false);
+ }
+
+ /**
+ * Remove a utility based on the interface that it implements
+ *
+ * @param utility The utility to remove
+ *
+ * @throws IllegalArgumentException if utility is null
+ */
+ public void removeUtility(Object utility) {
+ if (utility == null) {
+ throw new IllegalArgumentException("Cannot remove null as a Service");
+ }
+
+ Set<Class<?>> interfaces = getAllInterfaces(utility.getClass());
+ for (Class<?> i : interfaces) {
+ utilities.remove(i);
+ }
+ }
+
+ /**
+ * Returns the set of interfaces implemented by the given class and its
+ * ancestors or a blank set if none
+ */
+ private static Set<Class<?>> getAllInterfaces(Class<?> clazz) {
+ Set<Class<?>> implemented = new HashSet<Class<?>>();
+ getAllInterfaces(clazz, implemented);
+ return implemented;
+ }
+
+ private static void getAllInterfaces(Class<?> clazz, Set<Class<?>> implemented) {
+ Class<?>[] interfaces = clazz.getInterfaces();
+ for (Class<?> interfaze : interfaces) {
+ if (Modifier.isPublic(interfaze.getModifiers())) {
+ implemented.add(interfaze);
+ }
+ }
+ Class<?> superClass = clazz.getSuperclass();
+ // Object has no superclass so check for null
+ if (superClass != null && !superClass.equals(Object.class)) {
+ getAllInterfaces(superClass, implemented);
+ }
+ }
+
+ public <T> T getUtility(Class<T> utilityType, boolean newInstance) {
+ if (utilityType == null) {
+ throw new IllegalArgumentException("Cannot lookup Service of type null");
+ }
+
+ Object utility = null;
+ if (!newInstance) {
+ utility = utilities.get(utilityType);
+ }
+ if (utility == null) {
+
+ // Dynamically load a utility class declared under META-INF/services/"utilityType"
+ try {
+ ServiceDeclaration utilityDeclaration =
+ ServiceDiscovery.getInstance().getServiceDeclaration(utilityType.getName());
+ if (utilityDeclaration != null) {
+ Class<?> utilityClass = utilityDeclaration.loadClass();
+
+ // Construct the utility
+ Constructor<?>[] constructors = utilityClass.getConstructors();
+ Constructor<?> constructor = getConstructor(constructors, ExtensionPointRegistry.class, Map.class);
+ if (constructor != null) {
+ utility = constructor.newInstance(extensionPoints, utilityDeclaration.getAttributes());
+ } else {
+ constructor = getConstructor(constructors, ExtensionPointRegistry.class);
+ if (constructor != null) {
+ utility = constructor.newInstance(extensionPoints);
+ } else {
+ constructor = getConstructor(constructors);
+ if (constructor != null) {
+ utility = constructor.newInstance();
+ } else {
+ throw new IllegalArgumentException("No valid constructor is found for " + utilityClass);
+ }
+ }
+ }
+ // Cache the loaded utility
+ addUtility(utility);
+ }
+ } catch (InvocationTargetException e) {
+ throw new IllegalArgumentException(e);
+ } catch (IOException e) {
+ throw new IllegalArgumentException(e);
+ } catch (ClassNotFoundException e) {
+ throw new IllegalArgumentException(e);
+ } catch (InstantiationException e) {
+ throw new IllegalArgumentException(e);
+ } catch (IllegalAccessException e) {
+ throw new IllegalArgumentException(e);
+ }
+ }
+ return utilityType.cast(utility);
+ }
+
+}
diff --git a/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.java b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.java
new file mode 100644
index 0000000000..d5647d6601
--- /dev/null
+++ b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.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.core;
+
+
+/**
+ * The registry for the Tuscany core extension points. As the point of contact
+ * for all extension artifacts this registry allows loaded extensions to find
+ * all other parts of the system and register themselves appropriately.
+ *
+ * @version $Rev$ $Date$
+ */
+public interface ExtensionPointRegistry {
+
+ /**
+ * Add an extension point to the registry
+ * @param extensionPoint The instance of the extension point
+ *
+ * @throws IllegalArgumentException if extensionPoint is null
+ */
+ void addExtensionPoint(Object extensionPoint);
+
+ /**
+ * Get the extension point by the interface
+ * @param extensionPointType The lookup key (extension point interface)
+ * @return The instance of the extension point
+ *
+ * @throws IllegalArgumentException if extensionPointType is null
+ */
+ <T> T getExtensionPoint(Class<T> extensionPointType);
+
+ /**
+ * Remove an extension point
+ * @param extensionPoint The extension point to remove
+ *
+ * @throws IllegalArgumentException if extensionPoint is null
+ */
+ void removeExtensionPoint(Object extensionPoint);
+
+ /**
+ * Destroy the extension point registry
+ */
+ void destroy();
+}
diff --git a/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/FactoryExtensionPoint.java b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/FactoryExtensionPoint.java
new file mode 100644
index 0000000000..4d38cb8afe
--- /dev/null
+++ b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/FactoryExtensionPoint.java
@@ -0,0 +1,54 @@
+/*
+ * 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.core;
+
+/**
+ * An extension point for model factories. Model factories are provided to
+ * abstract the classes that represent artifacts in the assembly model away
+ * from their creation mechanism. When the runtime needs to extend the model
+ * as it reads in contributed artifacts it looks up the factory for the
+ * artifact required in this registry
+ *
+ * @version $Rev$ $Date$
+ */
+public interface FactoryExtensionPoint {
+
+ /**
+ * Add a model factory extension.
+ *
+ * @param factory The factory to add
+ */
+ void addFactory(Object factory);
+
+ /**
+ * Remove a model factory extension.
+ *
+ * @param factory The factory to remove
+ */
+ void removeFactory(Object factory);
+
+ /**
+ * Get a factory implementing the given interface.
+ * @param factoryInterface the lookup key (factory interface)
+ * @return The factory
+ */
+ <T> T getFactory(Class<T> factoryInterface);
+
+}
diff --git a/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivator.java b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivator.java
new file mode 100644
index 0000000000..dbfd0dcd90
--- /dev/null
+++ b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivator.java
@@ -0,0 +1,60 @@
+/*
+ * 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.core;
+
+
+/**
+ * ModuleActivator represents a module that plugs into the Tuscany system. Each
+ * module should provide an implementation of this interface and register the
+ * ModuleActivator implementation class by defining a file named
+ *
+ * "META-INF/services/org.apache.tuscany.core.ModuleActivator"
+ *
+ * The content of the file is the class name of the ModuleActivator implementation.
+ * The implementation class must have a no-arg constructor. The same instance
+ * will be used to invoke all the methods during different phases of the module
+ * activation. Note that the start and stop methods defined by this interface
+ * take a reference to the Tuscany SCA runtime ExtensionPointRegistry. This
+ * gives the ModuleActivator the opportunity to add extension points to the
+ * registry as it is requested to start up and remove them when it is requested
+ * to shut down.
+ *
+ * @version $Rev$ $Date$
+ */
+public interface ModuleActivator {
+
+ /**
+ * This method is invoked when the module is started by the Tuscany system.
+ * It can be used by this module to register extensions against extension
+ * points.
+ *
+ * @param registry The extension point registry
+ */
+ void start(ExtensionPointRegistry registry);
+
+ /**
+ * This method is invoked when the module is stopped by the Tuscany system.
+ * It can be used by this module to unregister extensions against the
+ * extension points.
+ *
+ * @param registry The extension point registry
+ */
+ void stop(ExtensionPointRegistry registry);
+}
diff --git a/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivatorExtensionPoint.java b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivatorExtensionPoint.java
new file mode 100644
index 0000000000..ec0f12b8ba
--- /dev/null
+++ b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivatorExtensionPoint.java
@@ -0,0 +1,53 @@
+/*
+ * 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.core;
+
+import java.util.List;
+
+
+/**
+ * The extension point for the Tuscany module activator extensions.
+ *
+ * @version $Rev$ $Date$
+ */
+public interface ModuleActivatorExtensionPoint {
+
+ /**
+ * Add a module activator extension to the extension point
+ * @param activator The instance of the module activator
+ *
+ * @throws IllegalArgumentException if activator is null
+ */
+ void addModuleActivator(ModuleActivator activator);
+
+ /**
+ * Returns the module activator extensions.
+ * @return The module activator extensions
+ */
+ List<ModuleActivator> getModuleActivators();
+
+ /**
+ * Remove a module activator
+ * @param activator The module activator to remove
+ *
+ * @throws IllegalArgumentException if activator is null
+ */
+ void removeModuleActivator(Object activator);
+}
diff --git a/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.java b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.java
new file mode 100644
index 0000000000..9804234850
--- /dev/null
+++ b/tags/java/sca/2.0-M3/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.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.core;
+
+
+/**
+ * The extension point for the Tuscany core utility extensions.
+ *
+ * @version $Rev$ $Date$
+ */
+public interface UtilityExtensionPoint {
+
+ /**
+ * Add a utility to the extension point
+ * @param utility The instance of the utility
+ *
+ * @throws IllegalArgumentException if utility is null
+ */
+ void addUtility(Object utility);
+
+ /**
+ * Get the utility by the interface
+ * @param utilityType The lookup key (utility interface)
+ * @return The instance of the utility
+ *
+ * @throws IllegalArgumentException if utilityType is null
+ */
+ <T> T getUtility(Class<T> utilityType);
+
+ /**
+ * Get a new instance of the utility by the interface
+ * @param utilityType The lookup key (utility interface)
+ * @param newInstance A new instance is required
+ * @return The instance of the utility
+ *
+ * @throws IllegalArgumentException if utilityType is null
+ */
+ <T> T getUtility(Class<T> utilityType, boolean newInstance);
+
+ /**
+ * Remove a utility
+ * @param utility The utility to remove
+ *
+ * @throws IllegalArgumentException if utility is null
+ */
+ void removeUtility(Object utility);
+}