1bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor/* 21d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Copyright (C) 2009 The Guava Authors 3bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 4bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Licensed under the Apache License, Version 2.0 (the "License"); 5bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * you may not use this file except in compliance with the License. 6bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * You may obtain a copy of the License at 7bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 8bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * http://www.apache.org/licenses/LICENSE-2.0 9bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 10bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Unless required by applicable law or agreed to in writing, software 11bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * distributed under the License is distributed on an "AS IS" BASIS, 12bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * See the License for the specific language governing permissions and 14bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * limitations under the License. 15bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 16bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 17bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorpackage com.google.common.util.concurrent; 18bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 191d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport com.google.common.annotations.Beta; 20bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport com.google.common.base.Throwables; 21bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 22bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorimport java.util.concurrent.Executor; 231d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport java.util.logging.Level; 241d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringertimport java.util.logging.Logger; 25bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 26bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor/** 27bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Base class for services that can implement {@link #startUp}, {@link #run} and 28bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * {@link #shutDown} methods. This class uses a single thread to execute the 29bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * service; consider {@link AbstractService} if you would like to manage any 30bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * threading manually. 31bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * 32bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * @author Jesse Wilson 331d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @since 1.0 34bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 351d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert@Beta 36bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnorpublic abstract class AbstractExecutionThreadService implements Service { 371d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert private static final Logger logger = Logger.getLogger( 381d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert AbstractExecutionThreadService.class.getName()); 391d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 40bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /* use AbstractService for state management */ 41bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor private final Service delegate = new AbstractService() { 42bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override protected final void doStart() { 43bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor executor().execute(new Runnable() { 441d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 45bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public void run() { 46bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor try { 47bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor startUp(); 48bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor notifyStarted(); 49bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 50bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor if (isRunning()) { 51bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor try { 52bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor AbstractExecutionThreadService.this.run(); 53bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } catch (Throwable t) { 54bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor try { 55bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor shutDown(); 561d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } catch (Exception ignored) { 571d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert logger.log(Level.WARNING, 581d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert "Error while attempting to shut down the service after failure.", ignored); 591d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 60bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor throw t; 61bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 62bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 63bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 64bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor shutDown(); 65bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor notifyStopped(); 66bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } catch (Throwable t) { 67bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor notifyFailed(t); 68bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor throw Throwables.propagate(t); 69bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 70bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 71bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor }); 72bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 73bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 74bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override protected void doStop() { 75bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor triggerShutdown(); 76bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 77bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor }; 78bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 79bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 80bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Start the service. This method is invoked on the execution thread. 81bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 82bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor protected void startUp() throws Exception {} 83bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 84bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 85bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Run the service. This method is invoked on the execution thread. 86bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Implementations must respond to stop requests. You could poll for lifecycle 87bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * changes in a work loop: 88bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * <pre> 89bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * public void run() { 90bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * while ({@link #isRunning()}) { 91bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * // perform a unit of work 92bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * } 93bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * } 94bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * </pre> 95bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * ...or you could respond to stop requests by implementing {@link 96bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * #triggerShutdown()}, which should cause {@link #run()} to return. 97bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 98bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor protected abstract void run() throws Exception; 99bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 100bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 101bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Stop the service. This method is invoked on the execution thread. 102bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 103bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor // TODO: consider supporting a TearDownTestCase-like API 104bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor protected void shutDown() throws Exception {} 105bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 106bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 107bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Invoked to request the service to stop. 108bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 109bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor protected void triggerShutdown() {} 110bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 111bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor /** 112bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Returns the {@link Executor} that will be used to run this service. 113bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * Subclasses may override this method to use a custom {@link Executor}, which 114bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * may configure its worker thread with a specific name, thread group or 115bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * priority. The returned executor's {@link Executor#execute(Runnable) 116bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * execute()} method is called when this service is started, and should return 117bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor * promptly. 1181d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 1191d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * <p>The default implementation returns a new {@link Executor} that sets the 1201d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * name of its threads to the string returned by {@link #getServiceName} 121bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor */ 122bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor protected Executor executor() { 123bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return new Executor() { 1241d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override 125bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor public void execute(Runnable command) { 1261d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert new Thread(command, getServiceName()).start(); 127bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 128bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor }; 129bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 130bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 131bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor @Override public String toString() { 1321d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return getServiceName() + " [" + state() + "]"; 133bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 134bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 135bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor // We override instead of using ForwardingService so that these can be final. 136bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 1371d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public final ListenableFuture<State> start() { 138bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return delegate.start(); 139bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 140bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 1411d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public final State startAndWait() { 142bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return delegate.startAndWait(); 143bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 144bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 1451d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public final boolean isRunning() { 146bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return delegate.isRunning(); 147bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 148bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 1491d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public final State state() { 150bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return delegate.state(); 151bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 152bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 1531d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public final ListenableFuture<State> stop() { 154bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return delegate.stop(); 155bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 156bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor 1571d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert @Override public final State stopAndWait() { 158bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor return delegate.stopAndWait(); 159bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor } 1601d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert 1611d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert /** 1621d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * Returns the name of this service. {@link AbstractExecutionThreadService} may include the name 1631d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * in debugging output. 1641d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 1651d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * <p>Subclasses may override this method. 1661d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * 1671d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert * @since 10.0 1681d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert */ 1691d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert protected String getServiceName() { 1701d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert return getClass().getSimpleName(); 1711d580d0f6ee4f21eb309ba7b509d2c6d671c4044Bjorn Bringert } 172bfe2dd089341dcb4c1fb65a5b6b077ad0ebbf6dcDan Egnor} 173