java 线程上机题循环唤醒三个线程轮流打印顺序 A线程->B线程->C线程

本文通过具体示例演示了如何使用Java的Lock和Condition来实现三个线程之间的协作与同步，确保它们按照预设的顺序轮流执行指定次数的任务。

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package cn.itcast.mybatis.dao;

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;


/**
 * 三个线程轮流打印 顺序    A线程->B线程->C线程
 * A线程打印5次   
 * B线程打印10次
 * C线程打印5次
 * 以上规则运行20轮
 * @author zhangkun
 *
 */
class ShareSoucre{
	Lock lock = new ReentrantLock();
	Condition condition1 = lock.newCondition();
	Condition condition2 = lock.newCondition();
	Condition condition3 = lock.newCondition();
	private int number = 1;
	
	public void sysa(){
		lock.lock();
		try {
			while(number != 1 ) condition1.await();
			for (int  i = 1;  i <= 5; i++) {
				System.out.println(Thread.currentThread().getName()+"--"+i+"A");
			}
			number = 2;
			condition2.signal();
		} catch (Exception e) {
			e.printStackTrace();
		}finally{
			lock.unlock();
		}
	}
	
	public void sysb(){
		lock.lock();
		try {
			while(number != 2 ) condition2.await();
			for (int  i = 1;  i <= 10; i++) {
				System.out.println(Thread.currentThread().getName()+"--"+i+"A");
			}
			number = 3;
			condition3.signal();
		} catch (Exception e) {
			e.printStackTrace();
		}finally{
			lock.unlock();
		}
	}
	
	public void sysc(){
		lock.lock();
		try {
			while(number != 3 ) condition3.await();
			for (int  i = 1;  i <= 5; i++) {
				System.out.println(Thread.currentThread().getName()+"--"+i+"A");
			}
			System.out.println();
			number = 1;
			condition1.signal();
		} catch (Exception e) {
			e.printStackTrace();
		}finally{
			lock.unlock();
		}
	}
}
public class MyClass3 {
	public static void main(String[] args) {
		final ShareSoucre shareSoucre = new ShareSoucre();
		
		new Thread(new Runnable() {
			@Override
			public void run() {
				for(int i = 0; i < 20; i++)shareSoucre.sysa();
			}
		},"AAA").start();
		
		new Thread(new Runnable() {
			@Override
			public void run() {
				for(int i = 0; i < 20; i++)shareSoucre.sysb();
			}
		},"BBB").start();
		
		new Thread(new Runnable() {
			@Override
			public void run() {
				for(int i = 0; i < 20; i++)shareSoucre.sysc();
			}
		},"CCC").start();
	}
}