自定义线程池和拒绝策略的使用

import java.util.concurrent.*;

/**          |-> 小于corePoolSize -> 分配线程执行
 * 任务提交-> |                                      |->成功->等待执行
 *           |-> 大于corePoolSize -> 提交到等待队列 ->|                   |->达到maximumPoolSize线程，提交失败->拒绝执行
 *                                                  |->失败->提交线程池->|
 *                                                                     |->未达到，提交成功->分配线程执行
 *
 *  自定义线程池和拒绝策略的使用
 */
public class RejectThreadPoolDemo {
    public static class MyTask implements Runnable{
        @Override
        public void run() {
            System.out.println(System.currentTimeMillis()+" Id:"+Thread.currentThread().getId());
            try {
                Thread.sleep(100);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
    public static void main(String[] args) throws InterruptedException{
        MyTask task = new MyTask();
        /**
         *  public ThreadPoolExecutor(int corePoolSize, //指定线程池中线程数量
         *                               int maximumPoolSize, //指定线程池中的最大线程数量
         *                               long keepAliveTime, //超过corePoolSize的空闲线程，在多长时间内会被销毁
         *                               TimeUnit unit, //keepAliveTime的单位
         *                               BlockingQueue<Runnable> workQueue,//任务队列
         *                               ThreadFactory threadFactory,//线程工厂，一般默认即可
         *                               RejectedExecutionHandler handler) {//拒绝策略，当任务太多来不及处理，如何拒绝任务
         */
        ThreadPoolExecutor executor = new ThreadPoolExecutor(5, 5, 0L,
                TimeUnit.MILLISECONDS, new LinkedBlockingDeque<>(10),
                Executors.defaultThreadFactory(), new RejectedExecutionHandler() {
            @Override
            public void rejectedExecution(Runnable r, ThreadPoolExecutor executor) { //r:请求执行的任务  executor:当前的线程池
                //打印丢失的任务
                System.out.println(r.toString() + " is discard");
            }
        });
        for (int i = 0; i < Integer.MAX_VALUE; i++) {
            executor.submit(task);
            Thread.sleep(10);
        }
    }
    //1567644472625 Id:9
    //1567644472631 Id:10
    //1567644472646 Id:11
    //1567644472654 Id:12
    //1567644472665 Id:13
    //java.util.concurrent.FutureTask@60e53b93 is discard
    //java.util.concurrent.FutureTask@5e2de80c is discard
    //。。。
}

自定义线程池和拒绝策略的使用

原文：https://www.cnblogs.com/fly-book/p/11462934.html