并且,在使用CachedThreadPool时,一定要注意控制任务的数量,否则,由于大量线程同时运行,很有会造成系统瘫痪。 三、submit()和execute()的区别 JDK5往后,任务分两类:一类是实现了Runnable接口的类,一类是实现了Callable接口的类。两者都可以被ExecutorService执行,它们的区别是: execute(Runnable x) 没有返回值。可以执行...
*/publicclassForkJoinMergeSort{publicstaticvoidmain(String[]args){ForkJoinPoolforkJoinPool=newForkJoinPool(6);int[]arr={3,2,6,1,7,10,2,3,5,6};Tasktask=newTask(arr,0,arr.length-1);forkJoinPool.invoke(task);for(inti:arr){System.out.println(i);}}staticclassTaskextendsRecursiveTask<Void...
fork方法将当前线程强制转换成ForkJoinWorkerThread,通过ForkJoinPool执行ForkJoinTask的线程都是该框架定义的ForkJoinWorkerThread,因此这种转换是正确的。如果不是利用ForkJoinPool线程池执行ForkJoinTask,将Thread强制转换成ForkJoinWorkerThread会抛出ClassCastException异常。 将任务加到队列后,由ForkJoinPool调度执行该任务。
用于构造公共池的参数可以通过设置以下 System#getProperty 系统属性来控制: - 并行度级别、非负整数 java.util.concurrent.ForkJoinPool.common.threadFactory - a ForkJoinWorkerThreadFactory类名。 ClassLoader#getSystemClassLoader() 系统类加载程序用于加载此类。 java.util.concurrent.ForkJoinPool.common.exception...
p.execute(newFibTask(8)); await(uehInvoked); }finally{ p.shutdownNow();// failure might have prevented processing task} } } 开发者ID:AdoptOpenJDK,项目名称:openjdk-jdk10,代码行数:28,代码来源:ForkJoinPoolTest.java 示例3: demo2_ForkJoin_execute_join ...
ForkJoinPool可以通过execute提交ForkJoinTask任务,然后通过ForkJoinWorkerThread.pushTask实现。 /** * Unless terminating, forks task if within an ongoing FJ computation in the * current pool, else submits as external task. */ private <T> void forkOrSubmit(ForkJoinTask<T> task) { ForkJoinWorker...
ForkJoinPool 需要通过ForkJoinPool来执行,任务分割出的子任务会添加到当前工作线程所维护的双端队列中,进入队列的头部。当一个工作线程的队列里暂时没有任务时,它会随机从其他工作线程的队列的尾部获取一个任务。 让我们通过一个简单的需求来使用下Fork/Join框架,需求是:计算1~8的累加结果。 使用Fork/Join框架首先...
If corePoolSize or more threads are running, the Executor always prefers queuing a request rather than adding a new thread. If a request cannot be queued, a new thread is created unless this would exceed maximumPoolSize, in which case, the task will be rejected. ...
timeExecute.addAndGet(System.nanoTime() - startTime);returnb; } } }publicstaticvoidmain(String[] args){finalAtomicIntegerthreadCount=newAtomicInteger(0);finalForkJoinPoolpool=newForkJoinPool(NUM_THREADS,newForkJoinPool.ForkJoinWorkerThreadFactory() {@OverridepublicForkJoinWorkerThreadnewThread(ForkJoin...
A ForkJoinPool differs from other kinds of ExecutorService mainly by virtue of employing work-stealing: all threads in the pool attempt to find and execute tasks submitted to the pool and/or created by other active tasks (eventually blocking waiting for work if none exist). This enables efficie...