newCachedThreadPool使用案例

newCachedThreadPool 缓存默认60s

猜下你的结果

package com.juc.threadpool;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * Created by Administrator on 2018/6/27.
 */
public class CachedThreadPoolDemo {

    public static void main(String[] args) throws InterruptedException {

        ExecutorService executorService = Executors.newCachedThreadPool();
        for (int i = 0; i < 10; i++) {
            final int s = i;
            executorService.execute(() -> {
                try {
                    System.out.println("" + s + ";;;" + Thread.currentThread().getName());
                } catch (Exception e) {
                    e.printStackTrace();
                }
            });
        }
        Thread.sleep(2000);//2s
        executorService.execute(() -> {
            try {

                System.out.println(";;;" + Thread.currentThread().getName());

            } catch (Exception e) {
                e.printStackTrace();
            }
        });

    }
}

线程被复用一次

package com.juc.threadpool;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

/**
 * Created by Administrator on 2018/6/27.
 */
public class CachedThreadPoolDemo {

    public static void main(String[] args) throws InterruptedException {

        ExecutorService cachedThreadPool = Executors.newCachedThreadPool();
        for (int i = 0; i < 10; i++) {
            final int index = i;
            try {
                System.out.println("睡起来...");
                Thread.sleep(index * 1000);
            } catch (Exception e) {
                e.printStackTrace();
            }
            cachedThreadPool.execute(new Runnable() {
                @Override
                public void run() {
                    System.out.println(index + "当前线程" + Thread.currentThread().getName());
                }
            });

        }

    }
}

线程被重用

缓存线程池无核心线程,队列只能存一个任务,导致它会无限创建线程

适合场景:流量洪峰一波一波的来,在线程没回收之前进行重复利用最好