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.mail.util;
016    
017    import com.liferay.mail.kernel.util.Hook;
018    import com.liferay.registry.Registry;
019    import com.liferay.registry.RegistryUtil;
020    import com.liferay.registry.ServiceTracker;
021    
022    /**
023     * @author Brian Wing Shun Chan
024     * @author Shuyang Zhou
025     * @author Peter Fellwock
026     */
027    public class HookFactory {
028    
029            public static Hook getInstance() {
030                    return _instance._serviceTracker.getService();
031            }
032    
033            private HookFactory() {
034                    Registry registry = RegistryUtil.getRegistry();
035    
036                    _serviceTracker = registry.trackServices(Hook.class);
037    
038                    _serviceTracker.open();
039            }
040    
041            private static final HookFactory _instance = new HookFactory();
042    
043            private final ServiceTracker<Hook, Hook> _serviceTracker;
044    
045    }