001 /* 002 * Sonar, open source software quality management tool. 003 * Copyright (C) 2008-2011 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.events; 021 022 import com.google.common.collect.Lists; 023 import org.sonar.api.batch.events.EventHandler; 024 025 import java.util.List; 026 027 /** 028 * Dispatches {@link BatchEvent}s. Eases decoupling by allowing objects to interact without having direct dependencies upon one another, and 029 * without requiring event sources to deal with maintaining handler lists. 030 */ 031 public class EventBus { 032 033 private EventHandler[] registeredHandlers; 034 035 public EventBus(EventHandler[] handlers) { 036 this.registeredHandlers = handlers; 037 } 038 039 /** 040 * Fires the given event. 041 */ 042 public void fireEvent(BatchEvent event) { 043 doFireEvent(event); 044 } 045 046 private void doFireEvent(BatchEvent event) { 047 List<EventHandler> handlers = getDispatchList(event.getType()); 048 for (EventHandler handler : handlers) { 049 event.dispatch(handler); 050 } 051 } 052 053 private List<EventHandler> getDispatchList(Class<? extends EventHandler> handlerType) { 054 List<EventHandler> result = Lists.newArrayList(); 055 for (EventHandler handler : registeredHandlers) { 056 if (handlerType.isAssignableFrom(handler.getClass())) { 057 result.add(handler); 058 } 059 } 060 return result; 061 } 062 063 }