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.portlet.exportimport.xstream;
016    
017    import com.liferay.registry.Registry;
018    import com.liferay.registry.RegistryUtil;
019    import com.liferay.registry.ServiceReference;
020    import com.liferay.registry.ServiceRegistration;
021    import com.liferay.registry.ServiceTracker;
022    import com.liferay.registry.ServiceTrackerCustomizer;
023    import com.liferay.registry.collections.ServiceRegistrationMap;
024    import com.liferay.registry.collections.ServiceRegistrationMapImpl;
025    
026    import java.util.Map;
027    import java.util.concurrent.ConcurrentHashMap;
028    
029    /**
030     * @author Mate Thurzo
031     */
032    public class XStreamAliasRegistryUtil {
033    
034            public static Map<Class<?>, String> getAliases() {
035                    return _instance._getAliases();
036            }
037    
038            public static void register(Class<?> clazz, String name) {
039                    _instance._register(clazz, name);
040            }
041    
042            public static void unregister(Class<?> clazz, String name) {
043                    _instance._unregister(clazz, name);
044            }
045    
046            private XStreamAliasRegistryUtil() {
047                    Registry registry = RegistryUtil.getRegistry();
048    
049                    _serviceTracker = registry.trackServices(
050                            XStreamAlias.class, new XStreamAliasServiceTrackerCustomizer());
051    
052                    _serviceTracker.open();
053            }
054    
055            private Map<Class<?>, String> _getAliases() {
056                    return _xstreamAliases;
057            }
058    
059            private void _register(Class<?> clazz, String name) {
060                    XStreamAlias xStreamAlias = new XStreamAlias(clazz, name);
061    
062                    Registry registry = RegistryUtil.getRegistry();
063    
064                    ServiceRegistration<XStreamAlias> serviceRegistration =
065                            registry.registerService(XStreamAlias.class, xStreamAlias);
066    
067                    _serviceRegistrations.put(xStreamAlias, serviceRegistration);
068            }
069    
070            private void _unregister(Class<?> clazz, String name) {
071                    XStreamAlias xStreamAlias = new XStreamAlias(clazz, name);
072    
073                    ServiceRegistration<XStreamAlias> serviceRegistration =
074                            _serviceRegistrations.remove(xStreamAlias);
075    
076                    if (serviceRegistration != null) {
077                            serviceRegistration.unregister();
078                    }
079            }
080    
081            private static final XStreamAliasRegistryUtil _instance =
082                    new XStreamAliasRegistryUtil();
083    
084            private final ServiceRegistrationMap<XStreamAlias> _serviceRegistrations =
085                    new ServiceRegistrationMapImpl<>();
086            private final ServiceTracker<XStreamAlias, XStreamAlias> _serviceTracker;
087            private final Map<Class<?>, String> _xstreamAliases =
088                    new ConcurrentHashMap<>();
089    
090            private class XStreamAliasServiceTrackerCustomizer
091                    implements ServiceTrackerCustomizer<XStreamAlias, XStreamAlias> {
092    
093                    @Override
094                    public XStreamAlias addingService(
095                            ServiceReference<XStreamAlias> serviceReference) {
096    
097                            Registry registry = RegistryUtil.getRegistry();
098    
099                            XStreamAlias xStreamAlias = registry.getService(serviceReference);
100    
101                            _xstreamAliases.put(
102                                    xStreamAlias.getClazz(), xStreamAlias.getName());
103    
104                            return xStreamAlias;
105                    }
106    
107                    @Override
108                    public void modifiedService(
109                            ServiceReference<XStreamAlias> serviceReference,
110                            XStreamAlias xStreamAlias) {
111                    }
112    
113                    @Override
114                    public void removedService(
115                            ServiceReference<XStreamAlias> serviceReference,
116                            XStreamAlias xStreamAlias) {
117    
118                            Registry registry = RegistryUtil.getRegistry();
119    
120                            registry.ungetService(serviceReference);
121    
122                            _xstreamAliases.remove(xStreamAlias.getClazz());
123                    }
124    
125            }
126    
127    }