Java tutorial
/* * RHQ Management Platform * Copyright (C) 2005-2008 Red Hat, Inc. * All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License, version 2, as * published by the Free Software Foundation, and/or the GNU Lesser * General Public License, version 2.1, also as published by the Free * Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License and the GNU Lesser General Public License * for more details. * * You should have received a copy of the GNU General Public License * and the GNU Lesser General Public License along with this program; * if not, write to the Free Software Foundation, Inc., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ package org.rhq.core.pc.plugin; import org.apache.commons.io.FileUtils; import org.rhq.core.clientapi.agent.PluginContainerException; import org.rhq.core.clientapi.descriptor.AgentPluginDescriptorUtil; import org.rhq.core.clientapi.descriptor.plugin.PluginDescriptor; import org.rhq.core.pc.PluginContainerConfiguration; import org.rhq.core.pluginapi.plugin.PluginContext; import org.rhq.core.pluginapi.plugin.PluginLifecycleListener; import org.testng.annotations.BeforeClass; import org.testng.annotations.Test; import java.io.File; import java.net.URL; import java.util.ArrayList; import java.util.Collection; import java.util.HashMap; import java.util.LinkedList; import java.util.List; import java.util.Map; import static org.testng.Assert.assertEquals; import static org.testng.Assert.assertNotNull; import static org.testng.Assert.assertTrue; public class PluginManagerTest { static final String PLUGIN_A = "plugin-A.jar"; static final String PLUGIN_B = "plugin-B-depends-on-A.jar"; static final String PLUGIN_C = "plugin-C-depends-on-B.jar"; PluginDescriptor descriptorA; PluginDescriptor descriptorB; PluginDescriptor descriptorC; @BeforeClass public void initClass() throws Exception { verifyPluginsExist(); initPluginDescriptors(); } void verifyPluginsExist() { assertPluginJarFileExists(PLUGIN_A); assertPluginJarFileExists(PLUGIN_B); assertPluginJarFileExists(PLUGIN_C); } void initPluginDescriptors() throws Exception { descriptorA = loadPluginDescriptor(getClass().getResource(PLUGIN_A)); descriptorB = loadPluginDescriptor(getClass().getResource(PLUGIN_B)); descriptorC = loadPluginDescriptor(getClass().getResource(PLUGIN_C)); } void assertPluginJarFileExists(String pluginPath) { URL pluginURL = getClass().getResource(pluginPath); File pluginJarFile = FileUtils.toFile(pluginURL); assertTrue(pluginJarFile.exists(), pluginJarFile.getAbsolutePath() + " does not exist and is needed for " + "tests in " + PluginManagerTest.class.getName()); } @Test public void initializeShouldLoadDiscoveredPlugins() throws Exception { PluginContainerConfiguration configuration = createConfiguration(); PluginManager pluginMgr = new PluginManager(); pluginMgr.setConfiguration(configuration); pluginMgr.initialize(); verifyThatPluginsAreLoaded(pluginMgr); } @Test public void pluginsShouldBeLoadedInCorrectOrder() throws Exception { PluginContainerConfiguration configuration = createConfiguration(); FakePluginLifecycleListenerManager pluginLifecycleListenerMgr = new FakePluginLifecycleListenerManager(); PluginManager pluginMgr = new PluginManager(); pluginMgr.setConfiguration(configuration); pluginMgr.setPluginLifecycleListenerManager(pluginLifecycleListenerMgr); pluginMgr.initialize(); verifyPluginsLoadedInCorrectOrder(pluginLifecycleListenerMgr); } @Test public void pluginsShouldBeShutdownInCorrectOrder() throws Exception { PluginContainerConfiguration configuration = createConfiguration(); FakePluginLifecycleListenerManager pluginLifecycleListenerMgr = new FakePluginLifecycleListenerManager(); PluginManager pluginMgr = new PluginManager(); pluginMgr.setConfiguration(configuration); pluginMgr.setPluginLifecycleListenerManager(pluginLifecycleListenerMgr); pluginMgr.initialize(); pluginMgr.shutdown(); verifyPluginsShutdownInCorrectOrder(pluginLifecycleListenerMgr); } private PluginContainerConfiguration createConfiguration() { PluginContainerConfiguration configuration = new PluginContainerConfiguration(); configuration.setPluginFinder(new PluginFinder() { public Collection<URL> findPlugins() { List<URL> pluginURLs = new ArrayList<URL>(); pluginURLs.add(getClass().getResource(PLUGIN_A)); pluginURLs.add(getClass().getResource(PLUGIN_B)); pluginURLs.add(getClass().getResource(PLUGIN_C)); return pluginURLs; } }); return configuration; } void verifyThatPluginsAreLoaded(PluginManager pluginMgr) throws Exception { assertPluginLoaded(descriptorA, pluginMgr); assertPluginLoaded(descriptorB, pluginMgr); assertPluginLoaded(descriptorC, pluginMgr); } void assertPluginLoaded(PluginDescriptor pluginDescriptor, PluginManager pluginMgr) throws Exception { PluginEnvironment pluginEnvironment = pluginMgr.getPlugin(pluginDescriptor.getName()); assertNotNull(pluginEnvironment, "Expected the '" + pluginDescriptor.getName() + "' plugin to be loaded."); } void verifyPluginsLoadedInCorrectOrder(FakePluginLifecycleListenerManager pluginLifecycleListenerMgr) throws Exception { assertPluginALoadedFirst(pluginLifecycleListenerMgr); assertPluginBLoadedSecond(pluginLifecycleListenerMgr); assertPluginCLoadedThird(pluginLifecycleListenerMgr); } void assertPluginALoadedFirst(FakePluginLifecycleListenerManager pluginLifecycleListenerMgr) throws Exception { int initOrder = pluginLifecycleListenerMgr.lifecycleTracker.getInitializationOrder(descriptorA.getName()); assertEquals(initOrder, 0, "Expected " + descriptorA.getName() + " to be initialized first."); } void assertPluginBLoadedSecond(FakePluginLifecycleListenerManager pluginLifecycleListenerMgr) throws Exception { int initOrder = pluginLifecycleListenerMgr.lifecycleTracker.getInitializationOrder(descriptorB.getName()); assertEquals(initOrder, 1, "Expected " + descriptorB.getName() + " to be initialized second."); } void assertPluginCLoadedThird(FakePluginLifecycleListenerManager pluginLifecycleListenerMgr) throws Exception { int initOrder = pluginLifecycleListenerMgr.lifecycleTracker.getInitializationOrder(descriptorC.getName()); assertEquals(initOrder, 2, "Expected " + descriptorC.getName() + " to be initialized third."); } void verifyPluginsShutdownInCorrectOrder(FakePluginLifecycleListenerManager pluginLifecycleListenerMgr) throws Exception { assertPluginCShutdownFirst(pluginLifecycleListenerMgr); assertPluginBShutdownSecond(pluginLifecycleListenerMgr); assertPluginAShutdownThird(pluginLifecycleListenerMgr); } void assertPluginCShutdownFirst(FakePluginLifecycleListenerManager pluginLifecycleListenerMgr) throws Exception { int shutdownOrder = pluginLifecycleListenerMgr.lifecycleTracker.getShutdownOrder(descriptorC.getName()); assertEquals(shutdownOrder, 0, "Expected " + descriptorC.getName() + " to be shutdown first."); } void assertPluginBShutdownSecond(FakePluginLifecycleListenerManager pluginLifecycleListenerMgr) throws Exception { int shutdownOrder = pluginLifecycleListenerMgr.lifecycleTracker.getShutdownOrder(descriptorB.getName()); assertEquals(shutdownOrder, 1, "Expected " + descriptorB.getName() + " to be shutdown second."); } void assertPluginAShutdownThird(FakePluginLifecycleListenerManager pluginLifecycleListenerMgr) throws Exception { int shutdownOrder = pluginLifecycleListenerMgr.lifecycleTracker.getShutdownOrder(descriptorA.getName()); assertEquals(shutdownOrder, 2, "Expected " + descriptorA.getName() + " to be shutdown third."); } PluginDescriptor loadPluginDescriptor(URL pluginURL) throws PluginContainerException { return AgentPluginDescriptorUtil.loadPluginDescriptorFromUrl(pluginURL); } static class FakePluginLifecycleListenerManager implements PluginLifecycleListenerManager { Map<String, PluginLifecycleListener> listeners = new HashMap<String, PluginLifecycleListener>(); PluginLifecycleTracker lifecycleTracker = new PluginLifecycleTracker(); public PluginLifecycleListener loadListener(PluginDescriptor pluginDescriptor, PluginEnvironment pluginEnvironment) throws PluginContainerException { FakePluginLifecycleListener listener = new FakePluginLifecycleListener(pluginDescriptor.getName(), lifecycleTracker); listeners.put(pluginDescriptor.getName(), listener); return listener; } public PluginLifecycleListener getListener(String pluginName) { return listeners.get(pluginName); } public void setListener(String pluginName, PluginLifecycleListener listener) { listeners.put(pluginName, listener); } public void shutdown() { } } /** * This is helper class that is used to track the order of start up and shutdown for the plugins used by these * tests. */ static class PluginLifecycleTracker { private List<String> initializedPlugins = new LinkedList<String>(); private List<String> shutdownPlugins = new LinkedList<String>(); public void initialize(String plugin) { initializedPlugins.add(plugin); } public void shutdown(String plugin) { shutdownPlugins.add(plugin); } public int getInitializationOrder(String plugin) { return initializedPlugins.indexOf(plugin); } public int getShutdownOrder(String plugin) { return shutdownPlugins.indexOf(plugin); } } static class FakePluginLifecycleListener implements PluginLifecycleListener { String pluginName; PluginLifecycleTracker lifecycleTracker; public FakePluginLifecycleListener(String pluginName, PluginLifecycleTracker lifecycleTracker) { this.pluginName = pluginName; this.lifecycleTracker = lifecycleTracker; } public void initialize(PluginContext context) throws Exception { lifecycleTracker.initialize(pluginName); } public void shutdown() { lifecycleTracker.shutdown(pluginName); } } }