/* * Copyright 2002-2016 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.scheduling.concurrent; import java.util.concurrent.ForkJoinPool; import java.util.concurrent.TimeUnit; import org.springframework.beans.factory.DisposableBean; import org.springframework.beans.factory.FactoryBean; import org.springframework.beans.factory.InitializingBean; /** * A Spring {@link FactoryBean} that builds and exposes a preconfigured {@link ForkJoinPool}. * * <p>For details on the ForkJoinPool API and its use with RecursiveActions, see the * <a href="http://docs.oracle.com/javase/7/docs/api/java/util/concurrent/ForkJoinPool.html">JDK 7 javadoc</a>. * * <p>{@code jsr166.jar}, containing {@code java.util.concurrent} updates for Java 6, can be obtained * from the <a href="http://gee.cs.oswego.edu/dl/concurrency-interest/">concurrency interest website</a>. * * @author Juergen Hoeller * @since 3.1 */ public class ForkJoinPoolFactoryBean implements FactoryBean<ForkJoinPool>, InitializingBean, DisposableBean { private boolean commonPool = false; private int parallelism = Runtime.getRuntime().availableProcessors(); private ForkJoinPool.ForkJoinWorkerThreadFactory threadFactory = ForkJoinPool.defaultForkJoinWorkerThreadFactory; private Thread.UncaughtExceptionHandler uncaughtExceptionHandler; private boolean asyncMode = false; private int awaitTerminationSeconds = 0; private ForkJoinPool forkJoinPool; /** * Set whether to expose JDK 8's 'common' {@link ForkJoinPool}. * <p>Default is "false", creating a local {@link ForkJoinPool} instance based on the * {@link #setParallelism "parallelism"}, {@link #setThreadFactory "threadFactory"}, * {@link #setUncaughtExceptionHandler "uncaughtExceptionHandler"} and * {@link #setAsyncMode "asyncMode"} properties on this FactoryBean. * <p><b>NOTE:</b> Setting this flag to "true" effectively ignores all other * properties on this FactoryBean, reusing the shared common JDK {@link ForkJoinPool} * instead. This is a fine choice on JDK 8 but does remove the application's ability * to customize ForkJoinPool behavior, in particular the use of custom threads. * @since 3.2 * @see java.util.concurrent.ForkJoinPool#commonPool() */ public void setCommonPool(boolean commonPool) { this.commonPool = commonPool; } /** * Specify the parallelism level. Default is {@link Runtime#availableProcessors()}. */ public void setParallelism(int parallelism) { this.parallelism = parallelism; } /** * Set the factory for creating new ForkJoinWorkerThreads. * Default is {@link ForkJoinPool#defaultForkJoinWorkerThreadFactory}. */ public void setThreadFactory(ForkJoinPool.ForkJoinWorkerThreadFactory threadFactory) { this.threadFactory = threadFactory; } /** * Set the handler for internal worker threads that terminate due to unrecoverable errors * encountered while executing tasks. Default is none. */ public void setUncaughtExceptionHandler(Thread.UncaughtExceptionHandler uncaughtExceptionHandler) { this.uncaughtExceptionHandler = uncaughtExceptionHandler; } /** * Specify whether to establish a local first-in-first-out scheduling mode for forked tasks * that are never joined. This mode (asyncMode = {@code true}) may be more appropriate * than the default locally stack-based mode in applications in which worker threads only * process event-style asynchronous tasks. Default is {@code false}. */ public void setAsyncMode(boolean asyncMode) { this.asyncMode = asyncMode; } /** * Set the maximum number of seconds that this ForkJoinPool is supposed to block * on shutdown in order to wait for remaining tasks to complete their execution * before the rest of the container continues to shut down. This is particularly * useful if your remaining tasks are likely to need access to other resources * that are also managed by the container. * <p>By default, this ForkJoinPool won't wait for the termination of tasks at all. * It will continue to fully execute all ongoing tasks as well as all remaining * tasks in the queue, in parallel to the rest of the container shutting down. * In contrast, if you specify an await-termination period using this property, * this executor will wait for the given time (max) for the termination of tasks. * <p>Note that this feature works for the {@link #setCommonPool "commonPool"} * mode as well. The underlying ForkJoinPool won't actually terminate in that * case but will wait for all tasks to terminate. * @see java.util.concurrent.ForkJoinPool#shutdown() * @see java.util.concurrent.ForkJoinPool#awaitTermination */ public void setAwaitTerminationSeconds(int awaitTerminationSeconds) { this.awaitTerminationSeconds = awaitTerminationSeconds; } @Override public void afterPropertiesSet() { this.forkJoinPool = (this.commonPool ? ForkJoinPool.commonPool() : new ForkJoinPool(this.parallelism, this.threadFactory, this.uncaughtExceptionHandler, this.asyncMode)); } @Override public ForkJoinPool getObject() { return this.forkJoinPool; } @Override public Class<?> getObjectType() { return ForkJoinPool.class; } @Override public boolean isSingleton() { return true; } @Override public void destroy() { // Ignored for the common pool. this.forkJoinPool.shutdown(); // Wait for all tasks to terminate - works for the common pool as well. if (this.awaitTerminationSeconds > 0) { try { this.forkJoinPool.awaitTermination(this.awaitTerminationSeconds, TimeUnit.SECONDS); } catch (InterruptedException ex) { Thread.currentThread().interrupt(); } } } }