转自：http://blog.csdn.net/hanlipenghanlipeng/article/details/52108446
package com.concurrency; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.ScheduledExecutorService; import java.util.concurrent.TimeUnit; /** * * @author Sailing * */ public class ThreadPool { private class HelloRunnable implements Runnable{ @Override public void run() { // TODO Auto-generated method stub String name = Thread.currentThread().getName(); System.out.println(name+"----it's runnable"); } } Runnable runnable = new HelloRunnable(); /** * 创建大小不固定的线程池 * * 如果线程池大小超过了处理任务所需要的线程 * 线程池就会回收空闲的线程池，当处理任务增加时，线程池可以增加线程来处理任务 * 线程池不会对线程的大小进行限制 * 线程池的大小依赖于操作系统 **/ ExecutorService es = Executors.newCachedThreadPool(); public void getThreadPool(){ for(int i=0;i<12;i++){ es.execute(runnable); // System.out.println("currentName----"+Thread.currentThread().getName()); try { //如果没有这一步，会出现多个不同的线程，也会有线程重用；如果使得主线程睡一下，那么只用一个线程就够了 Thread.sleep(0, 1); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } // System.out.println("isShutdown() : "+es.isShutdown()+" isTerminated "+es.isTerminated()); } es.shutdown(); } /** *Console 如果主线程不睡，会出现多个不同的线程，也会有线程重用 * pool-1-thread-1----it's runnable pool-1-thread-2----it's runnable pool-1-thread-3----it's runnable pool-1-thread-4----it's runnable pool-1-thread-3----it's runnable pool-1-thread-1----it's runnable pool-1-thread-4----it's runnable pool-1-thread-2----it's runnable pool-1-thread-5----it's runnable pool-1-thread-6----it's runnable pool-1-thread-7----it's runnable pool-1-thread-8----it's runnable * * Console 主线程睡一下 * pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable pool-1-thread-1----it's runnable */ /**创建具一个可重用的，有固定数量的线程池 * 每次提交一个任务就提交一个线程，直到线程达到线城池大小，就不会创建新线程了 * 线程池的大小达到最大后达到稳定不变，如果一个线程异常终止，则会创建新的线程 */ ExecutorService es1 = Executors.newFixedThreadPool(20); public void getThreadPool1(){ for(int i=0;i<12;i++){ es1.execute(runnable); } es1.shutdown(); } /** *Console 如果创建的线程池够用，不会重用。如果不够，则会重用 * pool-2-thread-3----it's runnable pool-2-thread-1----it's runnable pool-2-thread-2----it's runnable pool-2-thread-4----it's runnable pool-2-thread-5----it's runnable pool-2-thread-6----it's runnable pool-2-thread-8----it's runnable pool-2-thread-9----it's runnable pool-2-thread-10----it's runnable pool-2-thread-12----it's runnable pool-2-thread-11----it's runnable pool-2-thread-7----it's runnable */ /**创建只有一个线程的线程池 * 按照提交顺序执行 * 跟上个数量为1的是一样 */ ExecutorService es2 = Executors.newSingleThreadExecutor(); public void getThreadPool2(){ for(int i=0;i<12;i++){ es2.execute(runnable); } es2.shutdown(); } /** * Console * pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable pool-3-thread-1----it's runnable */ /** * 创建一个线程池，大小可以设置，此线程支持定时以及周期性的执行任务 定时任务 */ ScheduledExecutorService ses = Executors.newScheduledThreadPool(5); public void getScheduledTreadPool(){ ses.scheduleAtFixedRate(runnable, 0, 100, TimeUnit.MICROSECONDS);//参数1：执行的目标对象 参数2：延时多长时间开始执行 参数3：开始后，多长时间执行一次 参数4：时间单位 } /** * Console * pool-4-thread-5----it's runnable pool-4-thread-5----it's runnable pool-4-thread-5----it's runnable pool-4-thread-5----it's runnable pool-4-thread-2----it's runnable pool-4-thread-2----it's runnable pool-4-thread-2----it's runnable pool-4-thread-4----it's runnable pool-4-thread-4----it's runnable pool-4-thread-3----it's runnable pool-4-thread-3----it's runnable pool-4-thread-1----it's runnable pool-4-thread-1----it's runnable pool-4-thread-1----it's runnable */ public static void main(String[] args) { //new ThreadPool().getThreadPool(); //new ThreadPool().getThreadPool1(); //new ThreadPool().getThreadPool2(); new ThreadPool().getScheduledTreadPool(); } }