Java多线程之Exchanger

import java.util.concurrent.Exchanger;/** * Exchanger让两个线程可以互换信息。 * 例子中服务生线程往空的杯子里倒水，顾客线程从装满水的杯子里喝水， * 然后通过Exchanger双方互换杯子，服务生接着往空杯子里倒水，顾客接着喝水， * 然后交换，如此周而复始。 */public class ExchangerTest {// 描述一个装水的杯子public static class Cup{// 标识杯子是否有水private boolean full = false;public Cup(boolean full){this.full = full;}// 添水，假设需要5spublic void addWater(){if (!this.full){try {Thread.sleep(5000);} catch (InterruptedException e) {}this.full = true;}}// 喝水，假设需要10spublic void drinkWater(){if (this.full){try {Thread.sleep(10000);} catch (InterruptedException e) {}this.full = false;}}}public static void testExchanger() {//初始化一个Exchanger，并规定可交换的信息类型是杯子final Exchanger<Cup> exchanger = new Exchanger<Cup>();// 初始化一个空的杯子和装满水的杯子final Cup initialEmptyCup = new Cup(false); final Cup initialFullCup = new Cup(true);//服务生线程class Waiter implements Runnable {public void run() {Cup currentCup = initialEmptyCup;try {int i=0;while (i < 2){System.out.println("服务生开始往杯子中添水："+ System.currentTimeMillis());// 往空的杯子里加水currentCup.addWater();System.out.println("服务生添水完毕："+ System.currentTimeMillis());// 杯子满后和顾客的空杯子交换System.out.println("服务生等待与顾客交换杯子："+ System.currentTimeMillis());currentCup = exchanger.exchange(currentCup);System.out.println("服务生与顾客交换杯子完毕："+ System.currentTimeMillis());i++;}} catch (InterruptedException ex) {}}}//顾客线程class Customer implements Runnable {public void run() {Cup currentCup = initialFullCup;try {int i=0;while (i < 2){System.out.println("顾客开始喝水："+ System.currentTimeMillis());//把杯子里的水喝掉currentCup.drinkWater();System.out.println("顾客喝水完毕："+ System.currentTimeMillis());//将空杯子和服务生的满杯子交换System.out.println("顾客等待与服务生交换杯子："+ System.currentTimeMillis());currentCup = exchanger.exchange(currentCup);System.out.println("顾客与服务生交换杯子完毕："+ System.currentTimeMillis());i++;}} catch (InterruptedException ex) {}}}new Thread(new Waiter()).start();        new Thread(new Customer()).start();}public static void main(String[] args) {ExchangerTest.testExchanger();}}