001    /*
002     * Sonar, open source software quality management tool.
003     * Copyright (C) 2008-2012 SonarSource
004     * mailto:contact AT sonarsource DOT com
005     *
006     * Sonar is free software; you can redistribute it and/or
007     * modify it under the terms of the GNU Lesser General Public
008     * License as published by the Free Software Foundation; either
009     * version 3 of the License, or (at your option) any later version.
010     *
011     * Sonar is distributed in the hope that it will be useful,
012     * but WITHOUT ANY WARRANTY; without even the implied warranty of
013     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014     * Lesser General Public License for more details.
015     *
016     * You should have received a copy of the GNU Lesser General Public
017     * License along with Sonar; if not, write to the Free Software
018     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02
019     */
020    package org.sonar.batch.bootstrap;
021    
022    import org.picocontainer.ComponentAdapter;
023    import org.sonar.api.platform.ComponentContainer;
024    import org.sonar.api.platform.PluginMetadata;
025    
026    import java.util.List;
027    
028    /**
029     * Module describes group of components - {@link #configure()}.
030     * Several modules can be grouped together - {@link #install(Module)}, {@link #installChild(Module)}.
031     * <p/>
032     */
033    public abstract class Module {
034    
035      ComponentContainer container;
036    
037      /**
038       * @return this
039       */
040      public final Module init() {
041        return init(new ComponentContainer());
042      }
043    
044      /**
045       * @return this
046       */
047      private Module init(ComponentContainer container) {
048        this.container = container;
049        configure();
050        return this;
051      }
052    
053      /**
054       * Installs module into this module.
055       *
056       * @return this
057       */
058      public final Module install(Module module) {
059        module.init(container);
060        return this;
061      }
062    
063      /**
064       * Installs module into new scope - see http://picocontainer.org/scopes.html
065       *
066       * @return installed module
067       */
068      public final Module installChild(Module child) {
069        ComponentContainer childContainer = container.createChild();
070        child.init(childContainer);
071        return child;
072      }
073    
074      public final void uninstallChild() {
075        container.removeChild();
076      }
077    
078      /**
079       * @return this
080       */
081      public final Module start() {
082        container.startComponents();
083        doStart();
084        return this;
085      }
086    
087      protected void doStart() {
088        // empty method to be overridden
089      }
090    
091      /**
092       * @return this
093       */
094      public final Module stop() {
095        try {
096          doStop();
097          container.stopComponents();
098        } catch (Exception e) {
099          // ignore
100        }
101        return this;
102      }
103    
104      protected void doStop() {
105        // empty method to be overridden
106      }
107    
108      /**
109       * Implementation of this method must not contain conditional logic and just should contain several invocations of
110       * {@link #addCoreSingleton(Object)}, {@link #addExtension(org.sonar.api.platform.PluginMetadata, Object)} or {@link #addAdapter(ComponentAdapter)}.
111       */
112      protected abstract void configure();
113    
114      protected final void addCoreSingleton(Object component) {
115        container.addSingleton(component);
116      }
117    
118      protected final void declareExtension(PluginMetadata plugin, Object extension) {
119        container.declareExtension(plugin, extension);
120      }
121    
122      protected final void addExtension(PluginMetadata plugin, Object extension) {
123        container.addExtension(plugin, extension);
124      }
125    
126      protected final void addAdapter(ComponentAdapter<?> componentAdapter) {
127        container.addPicoAdapter(componentAdapter);
128      }
129    
130      public final <T> T getComponentByType(Class<T> componentType) {
131        return container.getComponentByType(componentType);
132      }
133    
134      public final Object getComponentByKey(Object key) {
135        return container.getComponentByKey(key);
136      }
137    
138      public final <T> List<T> getComponents(Class<T> componentType) {
139        return container.getComponentsByType(componentType);
140      }
141    }