线程间通信

Posted 2023-01-24 weixin_ancenhw

判断、干活、通知三步骤
this.wait()等待
this.notifyAll()通知其他线程
虚假唤醒if,因为是异步的，建议使用while避免异步唤醒操作

	//定义票数
	private int tickCount=0;


	//线程++
	public synchronized void tickeAdd() throws InterruptedException 
	  while(tickCount!=0)
	  	wait();
	  
		System.out.println("线程切换数据："+tickCount);
	  tickCount++;
      this.notifyAll();
	

	//线程--
	public synchronized void tickeReduce() throws InterruptedException 
		while(tickCount!=1)
			wait();
		
		System.out.println("线程切换数据："+tickCount);
		tickCount--;
		this.notifyAll();
	


	@Test
	public void contextLoads()
		RenrenApplicationTests renrenApplicationTests = new RenrenApplicationTests();
		for (int i = 0; i < 20; i++) 
			new Thread(()->
				try 
					renrenApplicationTests.tickeAdd();
				 catch (InterruptedException e) 
					e.printStackTrace();
				
				try 
					renrenApplicationTests.tickeReduce();
				 catch (InterruptedException e) 
					e.printStackTrace();
				
			).start();
		
	

 //定义票数
    private int tickCount = 0;

    private Lock lock = new ReentrantLock();

    private Condition condition = lock.newCondition();


    //线程++
    public void tickeAdd() throws InterruptedException 
        lock.lock();
        try 
            while (tickCount != 0) 
                condition.await();
            
            System.out.println("线程切换数据：" + tickCount);
            tickCount++;
            condition.signalAll();

         finally 
           lock.unlock();
        

    

    //线程--
    public void tickeReduce() throws InterruptedException 
        lock.lock();
        try 
            while (tickCount != 1) 
                condition.await();
            
            System.out.println("线程切换数据：" + tickCount);
            tickCount--;
            condition.signalAll();
         finally 
            lock.unlock();

        
    


    @Test
    public void contextLoads() 
        RenrenApplicationTests renrenApplicationTests = new RenrenApplicationTests();
        for (int i = 0; i < 20; i++) 
            new Thread(() -> 
                try 
                    renrenApplicationTests.tickeAdd();
                 catch (InterruptedException e) 
                    e.printStackTrace();
                
                try 
                    renrenApplicationTests.tickeReduce();
                 catch (InterruptedException e) 
                    e.printStackTrace();
                
            ).start();