多线程 - （六）ThreadPoolExecutor

我不是女神ヾ 2022-05-13 11:26 235阅读 0赞

## ThreadPoolExecutor执行过程 ##

![这里写图片描述][70]

测试代码

package com.ahut.essearch.thread;
    
    import org.junit.Test;
    
    import java.util.ArrayList;
    import java.util.List;
    import java.util.concurrent.*;
    
    /**
     * desc :
     * create_user : cheng
     * create_date : 2018/9/12 13:59
     */
    public class ThreadPoolExecutorTest { 
    
        @Test
        public void testThreadPool() throws ExecutionException, InterruptedException {
            // 核心线程数
            int corePoolSize = 10;
            // 最大线程数
            int maximumPoolSize = 20;
            // 线程最大空闲时间
            long keepAliveTime = 60;
            // 空闲时间单位
            TimeUnit unit = TimeUnit.SECONDS;
            // 存放任务的队列
            BlockingQueue<Runnable> workQueue = new ArrayBlockingQueue<>(1000);
            // 拒绝策略
            RejectedExecutionHandler handler = new ThreadPoolExecutor.DiscardPolicy();
    
            ThreadPoolExecutor executor = new ThreadPoolExecutor(corePoolSize, maximumPoolSize, keepAliveTime, unit, workQueue, handler);
    
            List<Future<String>> futureList = new ArrayList<>();
    
            for (int i = 0; i < 1000; i++) {
                int j = i;
                Future<String> future = executor.submit(() -> showThreadInfo(j)); System.out.println(String.format("任务数: %d, 完成任务数: %d, 活跃线程: %d, 队列里的任务数: %d, poolSize: %d", executor.getTaskCount(), executor.getCompletedTaskCount(), executor.getActiveCount(), executor.getQueue().size(), executor.getPoolSize())); futureList.add(future); } for (Future<String> future : futureList) { System.out.println(future.get()); } System.out.println(String.format("任务数: %d, 完成任务数: %d, 活跃线程: %d, 队列里的任务数: %d", executor.getTaskCount(), executor.getCompletedTaskCount(), executor.getActiveCount(), executor.getQueue().size())); executor.shutdown(); } public String showThreadInfo(int i) throws InterruptedException { Thread.sleep(500); return Thread.currentThread().getName() + " && " + i; } }

[70]: /images/20220513/13c711e0263447699aef5b828a78468d.png