利用AQS实现一个协作类-AQS开门

利用AQS实现一个协作类-AQS开门的实例代码如下所示:

package com.yang.aqs;

import java.util.concurrent.locks.AbstractQueuedSynchronizer;

/**
 * 我们模拟一个门,一个线程去开门,剩余的线程去等待开门
 */
public class MyLatch {
    private final Sync sync = new Sync();

    /**
     * 等待开门
     */
    public  void await() {
        sync.tryAcquire(0);
    }

    /**
     * 开门 把state设置为1
     */
    public void signal() {
        sync.tryRelease(0);
    }

    private class Sync extends AbstractQueuedSynchronizer {
        @Override
        protected int tryAcquireShared(int arg) {
            //如果小于0就要排队
            return (getState() == 1) ? 1 : -1;

        }

        @Override
        protected boolean tryReleaseShared(int arg) {
            setState(1);
            return true;
        }

        @Override
        protected boolean tryAcquire(int arg) {

            return (getState() == 1) ? true : false;
        }

        @Override
        protected boolean tryRelease(int arg) {
            setState(1);
            return true;
        }
    }

    public static void main(String[] args) {
        MyLatch myLatch = new MyLatch();
        for (int i = 0; i < 10; i++) {
            new Thread(new Runnable() {
                @Override
                public void run() {
                    System.out.println(Thread.currentThread().getName() + "尝试去打开门,打开失败,需要等待");
                    myLatch.await();
                    System.out.println(Thread.currentThread().getName() + "门开了,可以进去了");
                }
            }).start();
        }


    }
}

  

posted @ 2020-04-26 12:06  cnxieyang  阅读(200)  评论(0编辑  收藏  举报
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