001    /**
002     * Copyright (c) 2000-present Liferay, Inc. All rights reserved.
003     *
004     * This library is free software; you can redistribute it and/or modify it under
005     * the terms of the GNU Lesser General Public License as published by the Free
006     * Software Foundation; either version 2.1 of the License, or (at your option)
007     * any later version.
008     *
009     * This library is distributed in the hope that it will be useful, but WITHOUT
010     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
011     * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
012     * details.
013     */
014    
015    package com.liferay.portal.model;
016    
017    import com.liferay.portal.kernel.bean.ClassLoaderBeanHandler;
018    import com.liferay.portal.kernel.util.ProxyUtil;
019    import com.liferay.portal.kernel.util.ReflectionUtil;
020    import com.liferay.registry.Filter;
021    import com.liferay.registry.Registry;
022    import com.liferay.registry.RegistryUtil;
023    import com.liferay.registry.ServiceReference;
024    import com.liferay.registry.ServiceRegistration;
025    import com.liferay.registry.ServiceTracker;
026    import com.liferay.registry.ServiceTrackerCustomizer;
027    
028    import java.lang.reflect.InvocationHandler;
029    
030    import java.util.ArrayList;
031    import java.util.List;
032    import java.util.Map;
033    import java.util.concurrent.ConcurrentHashMap;
034    import java.util.concurrent.ConcurrentMap;
035    
036    /**
037     * @author Peter Fellwock
038     */
039    public class ModelListenerRegistrationUtil {
040    
041            public static <T> ModelListener<T>[] getModelListeners(Class<T> clazz) {
042                    return _instance._getModelListeners(clazz);
043            }
044    
045            public static void register(ModelListener<?> modelListener) {
046                    _instance._register(modelListener.getClass().getName(), modelListener);
047            }
048    
049            public static void unregister(ModelListener<?> modelListener) {
050                    _instance._unregister(modelListener.getClass().getName());
051            }
052    
053            private ModelListenerRegistrationUtil() {
054                    Registry registry = RegistryUtil.getRegistry();
055    
056                    Filter filter = registry.getFilter(
057                            "(objectClass=" + ModelListener.class.getName() + ")");
058    
059                    _serviceTracker = registry.trackServices(
060                            filter, new ModelListenerTrackerCustomizer());
061    
062                    _serviceTracker.open();
063            }
064    
065            private <T> ModelListener<T>[] _getModelListeners(Class<T> clazz) {
066                    List<ModelListener<?>> modelListeners = _modelListeners.get(clazz);
067    
068                    if (modelListeners == null) {
069                            modelListeners = new ArrayList<ModelListener<?>>();
070    
071                            List<ModelListener<?>> previousList = _modelListeners.putIfAbsent(
072                                    clazz, modelListeners);
073    
074                            if (previousList != null) {
075                                    modelListeners = previousList;
076                            }
077                    }
078    
079                    return modelListeners.toArray(new ModelListener[modelListeners.size()]);
080            }
081    
082            private <T> void _register(
083                    String className, ModelListener<T> modelListener) {
084    
085                    Registry registry = RegistryUtil.getRegistry();
086    
087                    ServiceRegistration<?> serviceRegistration = registry.registerService(
088                            ModelListener.class.getName(), modelListener);
089    
090                    _serviceRegistrations.put(className, serviceRegistration);
091            }
092    
093            private void _unregister(String className) {
094                    ServiceRegistration<?> serviceRegistration =
095                            _serviceRegistrations.remove(className);
096    
097                    if (serviceRegistration != null) {
098                            serviceRegistration.unregister();
099                    }
100            }
101    
102            private static final ModelListenerRegistrationUtil _instance =
103                    new ModelListenerRegistrationUtil();
104    
105            private final ConcurrentMap<Class<?>, List<ModelListener<?>>>
106                    _modelListeners =
107                            new ConcurrentHashMap<Class<?>, List<ModelListener<?>>>();
108            private final Map<String, ServiceRegistration<?>> _serviceRegistrations =
109                    new ConcurrentHashMap<String, ServiceRegistration<?>>();
110            private final ServiceTracker<ModelListener<?>, ModelListener<?>>
111                    _serviceTracker;
112    
113            private class ModelListenerTrackerCustomizer
114                    implements
115                            ServiceTrackerCustomizer<ModelListener<?>, ModelListener<?>> {
116    
117                    @Override
118                    public ModelListener<?> addingService(
119                            ServiceReference<ModelListener<?>> serviceReference) {
120    
121                            Registry registry = RegistryUtil.getRegistry();
122    
123                            ModelListener<?> modelListener = registry.getService(
124                                    serviceReference);
125    
126                            Class<?> clazz = _getModelListeners(modelListener);
127    
128                            if (clazz == null) {
129                                    return null;
130                            }
131    
132                            List<ModelListener<?>> modelListeners = _modelListeners.get(clazz);
133    
134                            if (modelListeners == null) {
135                                    modelListeners = new ArrayList<ModelListener<?>>();
136    
137                                    List<ModelListener<?>> previousModelListeners =
138                                            _modelListeners.putIfAbsent(clazz, modelListeners);
139    
140                                    if (previousModelListeners != null) {
141                                            modelListeners = previousModelListeners;
142                                    }
143                            }
144    
145                            modelListeners.add(modelListener);
146    
147                            return modelListener;
148                    }
149    
150                    @Override
151                    public void modifiedService(
152                            ServiceReference<ModelListener<?>> serviceReference,
153                            ModelListener<?> modelListener) {
154                    }
155    
156                    @Override
157                    public void removedService(
158                            ServiceReference<ModelListener<?>> serviceReference,
159                            ModelListener<?> modelListener) {
160    
161                            Registry registry = RegistryUtil.getRegistry();
162    
163                            registry.ungetService(serviceReference);
164    
165                            Class<?> clazz = _getModelListeners(modelListener);
166    
167                            List<ModelListener<?>> modelListeners = _modelListeners.get(clazz);
168    
169                            if (modelListeners != null) {
170                                    modelListeners.remove(modelListener);
171                            }
172                    }
173    
174                    private Class<?> _getModelListeners(ModelListener<?> modelListener) {
175                            Class<?> clazz = modelListener.getClass();
176    
177                            if (ProxyUtil.isProxyClass(clazz)) {
178                                    InvocationHandler invocationHandler =
179                                            ProxyUtil.getInvocationHandler(modelListener);
180    
181                                    if (invocationHandler instanceof ClassLoaderBeanHandler) {
182                                            ClassLoaderBeanHandler classLoaderBeanHandler =
183                                                    (ClassLoaderBeanHandler)invocationHandler;
184    
185                                            Object bean = classLoaderBeanHandler.getBean();
186    
187                                            clazz = bean.getClass();
188                                    }
189                            }
190    
191                            return ReflectionUtil.getGenericSuperType(clazz);
192                    }
193    
194            }
195    
196    }