diff options
Diffstat (limited to 'sandbox/event/modules/extensibility/src')
14 files changed, 1314 insertions, 0 deletions
diff --git a/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java new file mode 100644 index 0000000000..48f240559c --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultExtensionPointRegistry.java @@ -0,0 +1,184 @@ +/* + * 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.Map; +import java.util.Set; + +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 void addExtensionPoint(Object extensionPoint) { + if (extensionPoint == null) { + throw new IllegalArgumentException("Cannot register null as an ExtensionPoint"); + } + + Set<Class<?>> interfaces = getAllInterfaces(extensionPoint.getClass()); + for (Class<?> i : interfaces) { + 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 <T> T getExtensionPoint(Class<T> extensionPointType) { + if (extensionPointType == null) { + throw new IllegalArgumentException("Cannot lookup ExtensionPoint of type null"); + } + + Object extensionPoint = extensionPoints.get(extensionPointType); + if (extensionPoint == null) { + + // Dynamically load an extension point class declared under META-INF/services + try { + Class<?> extensionPointClass = + ServiceDiscovery.getInstance().loadFirstServiceClass(extensionPointType); + if (extensionPointClass != null) { + // 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); + } + } 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); + } + + /** + * 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 void removeExtensionPoint(Object extensionPoint) { + if (extensionPoint == null) { + throw new IllegalArgumentException("Cannot remove null as an ExtensionPoint"); + } + + Set<Class<?>> interfaces = getAllInterfaces(extensionPoint.getClass()); + for (Class<?> i : interfaces) { + 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); + } + } + +} diff --git a/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java new file mode 100644 index 0000000000..8ca030c0dd --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultModuleActivatorExtensionPoint.java @@ -0,0 +1,92 @@ +/* + * 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.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 to hold Tuscany module activators. + * + * @version $Rev$ $Date$ + */ +public class DefaultModuleActivatorExtensionPoint implements ModuleActivatorExtensionPoint { + 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 void loadModuleActivators() { + if (loadedActivators) + return; + + // Get the activator service declarations + Set<ServiceDeclaration> activatorDeclarations; + try { + activatorDeclarations = ServiceDiscovery.getInstance().getServiceDeclarations(ModuleActivator.class); + } catch (IOException e) { + throw new IllegalStateException(e); + } + + // Load and instantiate module activators + for (ServiceDeclaration activatorDeclaration: activatorDeclarations) { + ModuleActivator activator; + try { + Class<ModuleActivator> activatorClass = (Class<ModuleActivator>)activatorDeclaration.loadClass(); + activator = activatorClass.newInstance(); + } catch (ClassNotFoundException e) { + throw new IllegalArgumentException(e); + } catch (InstantiationException e) { + throw new IllegalArgumentException(e); + } catch (IllegalAccessException e) { + throw new IllegalArgumentException(e); + } + addModuleActivator(activator); + } + + loadedActivators = true; + } + +} diff --git a/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java new file mode 100644 index 0000000000..6f7c83c8d9 --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/DefaultUtilityExtensionPoint.java @@ -0,0 +1,184 @@ +/* + * 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.Map; +import java.util.Set; + +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 HashMap<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) { + if (utilityType == null) { + throw new IllegalArgumentException("Cannot lookup Service of type null"); + } + + Object utility = utilities.get(utilityType); + if (utility == null) { + + // Dynamically load a utility class declared under META-INF/utilities + try { + Class<?> utilityClass = + ServiceDiscovery.getInstance().loadFirstServiceClass(utilityType); + if (utilityClass != null) { + // Construct the utility + Constructor<?>[] constructors = utilityClass.getConstructors(); + Constructor<?> constructor = getConstructor(constructors, new Class<?>[] {ExtensionPointRegistry.class}); + if (constructor != null) { + utility = constructor.newInstance(extensionPoints); + } else { + constructor = getConstructor(constructors, new Class<?>[] {}); + 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); + } + + /** + * 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); + } + } + +} diff --git a/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.java new file mode 100644 index 0000000000..f2f67b2d52 --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ExtensionPointRegistry.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.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); +} diff --git a/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivator.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivator.java new file mode 100644 index 0000000000..dbfd0dcd90 --- /dev/null +++ b/sandbox/event/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/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivatorExtensionPoint.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/ModuleActivatorExtensionPoint.java new file mode 100644 index 0000000000..ec0f12b8ba --- /dev/null +++ b/sandbox/event/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/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.java new file mode 100644 index 0000000000..6b14b95666 --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/core/UtilityExtensionPoint.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; + + +/** + * 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); + + /** + * Remove a utility + * @param utility The utility to remove + * + * @throws IllegalArgumentException if utility is null + */ + void removeUtility(Object utility); +} diff --git a/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ContextClassLoaderServiceDiscoverer.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ContextClassLoaderServiceDiscoverer.java new file mode 100644 index 0000000000..2e11234095 --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ContextClassLoaderServiceDiscoverer.java @@ -0,0 +1,248 @@ +/* + * 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.extensibility; + +import java.io.BufferedReader; +import java.io.IOException; +import java.io.InputStream; +import java.io.InputStreamReader; +import java.lang.ref.WeakReference; +import java.net.URL; +import java.net.URLConnection; +import java.security.AccessController; +import java.security.PrivilegedAction; +import java.security.PrivilegedActionException; +import java.security.PrivilegedExceptionAction; +import java.util.Arrays; +import java.util.Collections; +import java.util.HashMap; +import java.util.HashSet; +import java.util.List; +import java.util.Map; +import java.util.Set; +import java.util.StringTokenizer; +import java.util.logging.Level; +import java.util.logging.Logger; + +/** + * A ServiceDiscoverer that find META-INF/services/... using the Context ClassLoader. + * + * @version $Rev: $ $Date: $ + */ +public class ContextClassLoaderServiceDiscoverer implements ServiceDiscoverer { + private static final Logger logger = Logger.getLogger(ContextClassLoaderServiceDiscoverer.class.getName()); + + public class ServiceDeclarationImpl implements ServiceDeclaration { + private URL url; + private String className; + private Class<?> javaClass; + private Map<String, String> attributes; + + public ServiceDeclarationImpl(URL url, String className, Map<String, String> attributes) { + super(); + this.url = url; + this.className = className; + this.attributes = attributes; + } + + public Map<String, String> getAttributes() { + return attributes; + } + + public String getClassName() { + return className; + } + + public URL getLocation() { + return url; + } + + public Class<?> loadClass() throws ClassNotFoundException { + if (className == null) { + return null; + } + if (javaClass == null) { + javaClass = loadClass(className); + } + return javaClass; + } + + public Class<?> loadClass(String className) throws ClassNotFoundException { + return classLoaderReference.get().loadClass(className); + } + + public String toString() { + StringBuffer sb = new StringBuffer(); + sb.append("ClassLoader: ").append(classLoaderReference.get()); + sb.append(" Attributes: ").append(attributes); + return sb.toString(); + } + + public URL getResource(final String name) { + return AccessController.doPrivileged(new PrivilegedAction<URL>() { + public URL run() { + return classLoaderReference.get().getResource(name); + } + }); + } + + } + + private WeakReference<ClassLoader> classLoaderReference; + + public ContextClassLoaderServiceDiscoverer() { + ClassLoader classLoader = Thread.currentThread().getContextClassLoader(); + this.classLoaderReference = new WeakReference<ClassLoader>(classLoader); + } + + private List<URL> getResources(final String name, final boolean firstOnly) throws IOException { + try { + return AccessController.doPrivileged(new PrivilegedExceptionAction<List<URL>>() { + public List<URL> run() throws IOException { + if (firstOnly) { + URL url = classLoaderReference.get().getResource(name); + if (url != null) { + return Arrays.asList(url); + } else { + return Collections.emptyList(); + } + } else { + List<URL> urls = Collections.list(classLoaderReference.get().getResources(name)); + return urls; + } + } + }); + } catch (PrivilegedActionException e) { + throw (IOException)e.getException(); + } + } + + /** + * Parse a service declaration in the form class;attr=value,attr=value and + * return a map of attributes + * + * @param declaration + * @return a map of attributes + */ + private static Map<String, String> parseServiceDeclaration(String declaration) { + Map<String, String> attributes = new HashMap<String, String>(); + int index = declaration.indexOf(';'); + if (index != -1) { + attributes.put("class", declaration.substring(0, index).trim()); + declaration = declaration.substring(index); + } else { + int j = declaration.indexOf('='); + if (j == -1) { + attributes.put("class", declaration.trim()); + return attributes; + } else { + declaration = ";" + declaration; + } + } + StringTokenizer tokens = new StringTokenizer(declaration); + for (; tokens.hasMoreTokens();) { + String key = tokens.nextToken("=").substring(1).trim(); + if (key == null) + break; + String value = tokens.nextToken(",").substring(1).trim(); + if (value == null) + break; + attributes.put(key, value); + } + return attributes; + } + + public Set<ServiceDeclaration> discover(String serviceName, boolean firstOnly) { + Set<ServiceDeclaration> descriptors = new HashSet<ServiceDeclaration>(); + + String name = "META-INF/services/" + serviceName; + boolean debug = logger.isLoggable(Level.FINE); + try { + for (final URL url : getResources(name, firstOnly)) { + if (debug) { + logger.fine("Reading service provider file: " + url.toExternalForm()); + } + + // Allow privileged access to open URL stream. Add FilePermission to added to security + // policy file. + InputStream is; + try { + is = AccessController.doPrivileged(new PrivilegedExceptionAction<InputStream>() { + public InputStream run() throws IOException { + URLConnection connection = url.openConnection(); + // TUSCANY-2539 + // Don't cache connections by default to stop Tuscany locking contribution jar files + // done here as this is one of the first places we open a stream and the only way to + // set the default is to set it on an instance of URLConnection + connection.setDefaultUseCaches(false); + connection.setUseCaches(false); + return url.openStream(); + } + }); + } catch (PrivilegedActionException e) { + throw (IOException)e.getException(); + } + BufferedReader reader = null; + try { + reader = new BufferedReader(new InputStreamReader(is)); + int count = 0; + while (true) { + String line = reader.readLine(); + if (line == null) + break; + line = line.trim(); + if (!line.startsWith("#") && !"".equals(line)) { + String reg = line.trim(); + if (debug) { + logger.fine("Registering service provider: " + reg); + } + + Map<String, String> attributes = parseServiceDeclaration(reg); + String className = attributes.get("class"); + if (className == null) { + // Add a unique class name to prevent equals() from returning true + className = "_class_" + count; + count++; + } + ServiceDeclarationImpl descriptor = new ServiceDeclarationImpl(url, className, attributes); + descriptors.add(descriptor); + if (firstOnly) { + return descriptors; + } + } + } + } finally { + if (reader != null) { + try { + reader.close(); + } catch (IOException e) { + // Ignore + } + } + } + } + } catch (IOException e) { + logger.log(Level.SEVERE, e.getMessage(), e); + } + return descriptors; + + } + +} diff --git a/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceDeclaration.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceDeclaration.java new file mode 100644 index 0000000000..403b6aa7a7 --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceDeclaration.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.extensibility; + +import java.net.URL; +import java.util.Map; + +/** + * Service declaration using J2SE Jar service provider spec Classes specified + * inside this declaration are loaded using the ClassLoader used to read the + * configuration file corresponding to this declaration. + * + * @version $Rev$ $Date$ + */ +public interface ServiceDeclaration { + /** + * Load a java class in the same context as the service definition + * @param className The class name + * @return The loaded class + * @throws ClassNotFoundException + */ + Class<?> loadClass(String className) throws ClassNotFoundException; + /** + * Get the java class for the service impl + * @return The java class + */ + Class<?> loadClass() throws ClassNotFoundException; + /** + * Get all attributes (name=value pairs) defined for the given entry + * @return All attributes keyed by name + */ + Map<String, String> getAttributes(); + + URL getLocation(); + + String getClassName(); + + URL getResource(String name); + + /** + * The service descriptor might be hashed + * @param obj Another object + * @return + */ + boolean equals(Object obj); + /** + * The service descriptor might be hashed + * @return + */ + int hashCode(); +} diff --git a/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceDiscoverer.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceDiscoverer.java new file mode 100644 index 0000000000..1722cd5f49 --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceDiscoverer.java @@ -0,0 +1,37 @@ +/* + * 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.extensibility; + +import java.util.Set; + +/** + * A SPI that allows different implementations of discovering service declarations + */ +public interface ServiceDiscoverer { + /** + * Discover the service descriptors by name + * @param serviceName The name of the service + * @param firstOnly A flag to indicate if only the first instance is to be discovered + * + * @return A set of service descriptors + */ + Set<ServiceDeclaration> discover(String serviceName, boolean firstOnly); + +} diff --git a/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceDiscovery.java b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceDiscovery.java new file mode 100644 index 0000000000..ce41a44068 --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/java/org/apache/tuscany/sca/extensibility/ServiceDiscovery.java @@ -0,0 +1,170 @@ +/* + * 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.extensibility; + +import java.io.IOException; +import java.lang.reflect.InvocationTargetException; +import java.lang.reflect.Method; +import java.security.AccessController; +import java.security.PrivilegedAction; +import java.util.HashSet; +import java.util.Set; +import java.util.logging.Level; +import java.util.logging.Logger; + +/** + * Service discovery for Tuscany based on J2SE Jar service provider spec. + * Services are described using configuration files in META-INF/services. + * Service description specifies a class name followed by optional properties. + * + * + * @version $Rev$ $Date$ + */ +public class ServiceDiscovery { + private static final Logger logger = Logger.getLogger(ServiceDiscovery.class.getName()); + + private final static ServiceDiscovery INSTANCE = new ServiceDiscovery(); + + private ServiceDiscoverer discoverer; + private Set<ClassLoader> registeredClassLoaders = new HashSet<ClassLoader>(); + + /** + * Get an instance of Service discovery, one instance is created per + * ClassLoader that this class is loaded from + * + * @return + */ + public static ServiceDiscovery getInstance() { + return INSTANCE; + } + + public ServiceDiscoverer getServiceDiscoverer() { + if (discoverer == null) { + discoverer = new ContextClassLoaderServiceDiscoverer(); + } + return discoverer; + } + + public void setServiceDiscoverer(ServiceDiscoverer sd) { + if (discoverer != null) { + throw new IllegalStateException("The ServiceDiscoverer cannot be reset"); + } + discoverer = sd; + } + + /** + * @deprecated + * Register a ClassLoader with this discovery mechanism. Tuscany extension + * ClassLoaders are registered here. + * + * @param classLoader + */ + @Deprecated + public synchronized void registerClassLoader(ClassLoader classLoader) { + registeredClassLoaders.add(classLoader); + } + + /** + * @deprecated + * Unregister a ClassLoader with this discovery mechanism. + * + * @param classLoader + */ + @Deprecated + public synchronized void unregisterClassLoader(ClassLoader classLoader) { + registeredClassLoaders.remove(classLoader); + } + + /** + * Get all service declarations for this name + * + * @param name + * @return set of service declarations + * @throws IOException + */ + public Set<ServiceDeclaration> getServiceDeclarations(String name) throws IOException { + Set<ServiceDeclaration> services = getServiceDiscoverer().discover(name, false); + return services; + } + + /** + * Get all service declarations for this interface + * + * @param serviceInterface + * @return set of service declarations + * @throws IOException + */ + public Set<ServiceDeclaration> getServiceDeclarations(Class<?> serviceInterface) throws IOException { + + return getServiceDeclarations(serviceInterface.getName()); + } + + /** + * Load one service implementation class for this interface + * + * @param serviceInterface + * @return service implementation class + * @throws IOException + * @throws ClassNotFoundException + */ + public Class<?> loadFirstServiceClass(final Class<?> serviceInterface) throws IOException, ClassNotFoundException { + // Try System property first + String className = AccessController.doPrivileged(new PrivilegedAction<String>() { + public String run() { + return System.getProperty(serviceInterface.getName()); + } + }); + if (className != null) { + try { + // Try the classloader for the service interface first + return Class.forName(className, false, serviceInterface.getClassLoader()); + } catch (ClassNotFoundException e) { + try { + // Try the thread context classloader + return Class.forName(className, false, Thread.currentThread().getContextClassLoader()); + } catch (ClassNotFoundException ex) { + logger.log(Level.WARNING, ex.getMessage(), ex); + } + } + } + Set<ServiceDeclaration> services = getServiceDiscoverer().discover(serviceInterface.getName(), true); + if (services.isEmpty()) { + return null; + } + return services.iterator().next().loadClass(); + } + + /** + * Create a new instance of a factory service class. + * + * @param serviceInterface + * @return service implementation class + * @throws SecurityException + * @throws NoSuchMethodException + * @throws InvocationTargetException + * @throws IllegalAccessException + */ + public Object newFactoryClassInstance(final Class<?> serviceInterface) throws SecurityException, NoSuchMethodException, InvocationTargetException, IllegalAccessException { + Method newInstanceMethod = serviceInterface.getMethod("newInstance"); + Object factory = newInstanceMethod.invoke(null); + return factory; + } + +} diff --git a/sandbox/event/modules/extensibility/src/main/resources/META-INF/services/org.apache.tuscany.sca.core.ModuleActivatorExtensionPoint b/sandbox/event/modules/extensibility/src/main/resources/META-INF/services/org.apache.tuscany.sca.core.ModuleActivatorExtensionPoint new file mode 100644 index 0000000000..42bad63132 --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/resources/META-INF/services/org.apache.tuscany.sca.core.ModuleActivatorExtensionPoint @@ -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.core.DefaultModuleActivatorExtensionPoint
diff --git a/sandbox/event/modules/extensibility/src/main/resources/META-INF/services/org.apache.tuscany.sca.core.UtilityExtensionPoint b/sandbox/event/modules/extensibility/src/main/resources/META-INF/services/org.apache.tuscany.sca.core.UtilityExtensionPoint new file mode 100644 index 0000000000..d769bad283 --- /dev/null +++ b/sandbox/event/modules/extensibility/src/main/resources/META-INF/services/org.apache.tuscany.sca.core.UtilityExtensionPoint @@ -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.core.DefaultUtilityExtensionPoint
diff --git a/sandbox/event/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/ContextClassLoaderServiceDiscovererTestCase.java b/sandbox/event/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/ContextClassLoaderServiceDiscovererTestCase.java new file mode 100644 index 0000000000..fd508402fc --- /dev/null +++ b/sandbox/event/modules/extensibility/src/test/java/org/apache/tuscany/sca/extensibility/ContextClassLoaderServiceDiscovererTestCase.java @@ -0,0 +1,72 @@ +/* + * 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.extensibility; + +import java.util.Set; + +import junit.framework.Assert; + +import org.junit.AfterClass; +import org.junit.BeforeClass; +import org.junit.Test; + +/** + * Test Case for ClasspathServiceDiscover + */ +public class ContextClassLoaderServiceDiscovererTestCase { + private static ContextClassLoaderServiceDiscoverer discover; + + /** + * @throws java.lang.Exception + */ + @BeforeClass + public static void setUpBeforeClass() throws Exception { + discover = new ContextClassLoaderServiceDiscoverer(); + } + + @Test + public void testDiscovery() { + Set<ServiceDeclaration> discriptors = + discover.discover("org.apache.tuscany.sca.core.ModuleActivatorExtensionPoint", false); + Assert.assertEquals(1, discriptors.size()); + discriptors = + discover.discover("notthere", false); + Assert.assertEquals(0, discriptors.size()); + } + + @Test + public void testDiscoveryFirst() { + Set<ServiceDeclaration> discriptors = + discover.discover("org.apache.tuscany.sca.core.ModuleActivatorExtensionPoint", true); + Assert.assertEquals(1, discriptors.size()); + discriptors = + discover.discover("notthere", true); + Assert.assertEquals(0, discriptors.size()); + } + + + /** + * @throws java.lang.Exception + */ + @AfterClass + public static void tearDownAfterClass() throws Exception { + } + +} |