001 /* 002 * Copyright (C) 2012 eXo Platform SAS. 003 * 004 * This is free software; you can redistribute it and/or modify it 005 * under the terms of the GNU Lesser General Public License as 006 * published by the Free Software Foundation; either version 2.1 of 007 * the License, or (at your option) any later version. 008 * 009 * This software is distributed in the hope that it will be useful, 010 * but WITHOUT ANY WARRANTY; without even the implied warranty of 011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 012 * Lesser General Public License for more details. 013 * 014 * You should have received a copy of the GNU Lesser General Public 015 * License along with this software; if not, write to the Free 016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 018 */ 019 package org.crsh.plugin; 020 021 import java.util.ArrayList; 022 import java.util.ServiceConfigurationError; 023 import java.util.ServiceLoader; 024 import java.util.logging.Level; 025 import java.util.logging.Logger; 026 027 public class ServiceLoaderDiscovery implements PluginDiscovery { 028 029 /** . */ 030 private static final Logger log = Logger.getLogger(PluginManager.class.getName()); 031 032 /** . */ 033 private final ClassLoader classLoader; 034 035 /** 036 * Create a new instance. 037 * 038 * @param classLoader the loader for the discovery 039 * @throws NullPointerException if the loader argument is null 040 */ 041 public ServiceLoaderDiscovery(ClassLoader classLoader) throws NullPointerException { 042 if (classLoader == null) { 043 throw new NullPointerException(); 044 } 045 046 // 047 this.classLoader = classLoader; 048 } 049 050 public Iterable<CRaSHPlugin<?>> getPlugins() { 051 052 // 053 ArrayList<CRaSHPlugin<?>> plugins = new ArrayList<CRaSHPlugin<?>>(); 054 try { 055 ServiceLoader<CRaSHPlugin> loader = ServiceLoader.load(CRaSHPlugin.class, classLoader); 056 for (CRaSHPlugin<?> plugin : loader) { 057 log.log(Level.INFO, "Loaded plugin " + plugin); 058 plugins.add(plugin); 059 } 060 } 061 catch (ServiceConfigurationError e) { 062 log.log(Level.SEVERE, "Could not load plugins", e); 063 } 064 065 // 066 return plugins; 067 } 068 }