按序交替打印ABC 按序交替打印ABC

package com.atguigu.juc;
【按序交替打印ABC】import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/*

编写一个程序，开启 3 个线程，这三个线程的 ID 分别为 A、B、C，每个线程将自己的 ID 在屏幕上打印 10 遍，要求输出的结果必须按顺序显示。
如：ABCABCABC…… 依次递归
*/
public class TestAlternate {
public static void main(String[] args) {
AlternateDemo ad = new AlternateDemo();

new Thread(new Runnable() {@Override public void run() { for (int i = 1; i <= 10; i++) { ad.loopA(i); } } }, "A").start(); new Thread(new Runnable() {@Override public void run() { for (int i = 1; i <= 10; i++) { ad.loopB(i); } } }, "B").start(); new Thread(new Runnable() {@Override public void run() { for (int i = 1; i <= 10; i++) { ad.loopC(i); } } }, "C").start();

}

}
class AlternateDemo{

private int number = 1; //用于判断执行线程的标记private Lock lock = new ReentrantLock(); private Condition c1 = lock.newCondition(); private Condition c2 = lock.newCondition(); private Condition c3 = lock.newCondition(); public void loopA(int totalLoop){ lock.lock(); try {//判断 if(number != 1){ try { c1.await(); } catch (InterruptedException e) { } }//打印 for (int i = 1; i <= 1; i++) { System.out.println(Thread.currentThread().getName() + " : " + i + " : " + totalLoop); }//唤醒 number = 2; c2.signal(); } finally { lock.unlock(); } }public void loopB(int totalLoop){ lock.lock(); try {//判断 if(number != 2){ try { c2.await(); } catch (InterruptedException e) { } }//打印 for (int i = 1; i <= 1; i++) { System.out.println(Thread.currentThread().getName() + " : " + i + " : " + totalLoop); }//唤醒 number = 3; c3.signal(); } finally { lock.unlock(); } }public void loopC(int totalLoop){ lock.lock(); try {//判断 if(number != 3){ try { c3.await(); } catch (InterruptedException e) { } }//打印 for (int i = 1; i <= 1; i++) { System.out.println(Thread.currentThread().getName() + " : " + i + " : " + totalLoop); }//唤醒 number = 1; c1.signal(); } finally { lock.unlock(); } }

}