| /* |
| * 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.felix.dm.impl; |
| |
| import java.util.ArrayList; |
| import java.util.Enumeration; |
| import java.util.List; |
| import java.util.Properties; |
| |
| import org.apache.felix.dm.DependencyManager; |
| import org.apache.felix.dm.dependencies.Dependency; |
| import org.apache.felix.dm.dependencies.ServiceDependency; |
| import org.apache.felix.dm.service.Service; |
| import org.apache.felix.dm.service.ServiceStateListener; |
| import org.osgi.framework.Constants; |
| import org.osgi.framework.ServiceReference; |
| |
| /** |
| * Aspect Service implementation. This class extends the FilterService in order to catch |
| * some Service methods for configuring actual aspect service implementation. |
| */ |
| public class AspectServiceImpl extends FilterService |
| { |
| public AspectServiceImpl(DependencyManager dm, Class aspectInterface, String aspectFilter, int ranking, String autoConfig) |
| { |
| super(dm.createService()); // This service will be filtered by our super class, allowing us to take control. |
| m_service.setImplementation(new AspectImpl(aspectInterface, aspectFilter, ranking, autoConfig)) |
| .add(dm.createServiceDependency() |
| .setService(aspectInterface, createAspectFilter(aspectFilter)) |
| .setAutoConfig(false) |
| .setCallbacks("added", "removed")); |
| } |
| |
| private String createAspectFilter(String filter) { |
| // we only want to match services which are not themselves aspects |
| if (filter == null || filter.length() == 0) { |
| return "(!(" + DependencyManager.ASPECT + "=*))"; |
| } |
| else { |
| return "(&(!(" + DependencyManager.ASPECT + "=*))" + filter + ")"; |
| } |
| } |
| |
| /** |
| * This class is the Aspect Implementation. It will create the actual Aspect Service, and |
| * will use the Aspect Service parameters provided by our enclosing class. |
| */ |
| class AspectImpl extends AbstractDecorator { |
| private final Class m_aspectInterface; // the service decorated by this aspect |
| private final String m_aspectFilter; // the service filter decorated by this aspect |
| private final int m_ranking; // the aspect ranking |
| private final String m_field; // the aspect impl field name where to inject decorated service |
| |
| public AspectImpl(Class aspectInterface, String aspectFilter, int ranking, String field) { |
| m_aspectInterface = aspectInterface; |
| m_aspectFilter = aspectFilter; |
| m_ranking = ranking; |
| m_field = field; |
| } |
| |
| public Service createService(Object[] params) { |
| List dependencies = m_service.getDependencies(); |
| // remove our internal dependency |
| dependencies.remove(0); |
| Properties serviceProperties = getServiceProperties(params); |
| String[] serviceInterfaces = getServiceInterfaces(); |
| Service service = m_manager.createService() |
| .setInterface(serviceInterfaces, serviceProperties) |
| .setImplementation(m_serviceImpl) |
| .setFactory(m_factory, m_factoryCreateMethod) // if not set, no effect |
| .setComposition(m_compositionInstance, m_compositionMethod) // if not set, no effect |
| .setCallbacks(m_callbackObject, m_init, m_start, m_stop, m_destroy) // if not set, no effect |
| .add(dependencies) |
| .add(getAspectDependency()); |
| for (int i = 0; i < m_stateListeners.size(); i ++) { |
| service.addStateListener((ServiceStateListener) m_stateListeners.get(i)); |
| } |
| return service; |
| } |
| |
| private Properties getServiceProperties(Object[] params) { |
| ServiceReference ref = (ServiceReference) params[0]; |
| Object service = params[1]; |
| Properties props = new Properties(); |
| // first add our aspect property |
| props.put(DependencyManager.ASPECT, ref.getProperty(Constants.SERVICE_ID)); |
| // and the ranking |
| props.put(Constants.SERVICE_RANKING, Integer.valueOf(m_ranking)); |
| String[] keys = ref.getPropertyKeys(); |
| for (int i = 0; i < keys.length; i++) { |
| props.put(keys[i], ref.getProperty(keys[i])); |
| } |
| if (m_serviceProperties != null) { |
| Enumeration e = m_serviceProperties.keys(); |
| while (e.hasMoreElements()) { |
| Object key = e.nextElement(); |
| props.put(key, m_serviceProperties.get(key)); |
| } |
| } |
| return props; |
| } |
| |
| private String[] getServiceInterfaces() |
| { |
| List serviceNames = new ArrayList(); |
| // Of course, we provide the aspect interface. |
| serviceNames.add(m_aspectInterface.getName()); |
| // But also append additional aspect implementation interfaces. |
| if (m_serviceInterfaces != null) { |
| for (int i = 0; i < m_serviceInterfaces.length; i ++) { |
| if (! m_serviceInterfaces[i].equals(m_aspectInterface.getName())) { |
| serviceNames.add(m_serviceInterfaces[i]); |
| } |
| } |
| } |
| return (String[]) serviceNames.toArray(new String[serviceNames.size()]); |
| } |
| |
| private Dependency getAspectDependency() { |
| ServiceDependency sd = |
| m_manager.createServiceDependency() |
| .setService(m_aspectInterface, createAspectFilter(m_aspectFilter)) |
| .setRequired(true); |
| |
| if (m_field != null) { |
| sd.setAutoConfig(m_field); |
| } |
| return sd; |
| } |
| |
| private String createAspectFilter(String filter) { |
| if (filter == null || filter.length() == 0) { |
| return "(|(!(" + Constants.SERVICE_RANKING + "=*))(" + Constants.SERVICE_RANKING + "<=" + (m_ranking - 1) + "))"; |
| } else { |
| return "(&(|(!(" + Constants.SERVICE_RANKING + "=*))(" + Constants.SERVICE_RANKING + "<=" + (m_ranking - 1) + "))" + filter + ")"; |
| } |
| } |
| } |
| } |