多线程模拟生产者消费者示例之wait/notify

public class Test {

    public static void main(String[] args) throws InterruptedException {
        List<String> queue = new ArrayList<>();
        new Thread(new PThread(queue)).start();
        new Thread(new CThread(queue)).start();
    }
}

/**
 * 生产者
 */
class PThread implements Runnable {
    private List<String> queue;
    private AtomicInteger i = new AtomicInteger();

    public PThread(List<String> queue) {
        this.queue = queue;
    }

    @Override
    public void run() {
        while (true) {
           synchronized(queue){
               //如果queue有元素,那么就释放锁吧
               if (queue.size() == 1) {
                   try {
                       queue.wait();// 释放锁
                   } catch (InterruptedException e) {
                       e.printStackTrace();
                   }
               } else {  //没有元素就生产一个元素
                   try {
                       Thread.sleep(1000);
                   } catch (InterruptedException e) {
                       e.printStackTrace();
                   }
                   String data = i.getAndIncrement() + "";
                   queue.add(data);
                   System.out.println("生产者线程,生产一个元素:"+data);
                   queue.notify();   //唤醒本线程,就可以获取锁了
               }
            }
        }
    }
}

/**
 * 消费者
 */
class CThread implements Runnable {
    private List<String> queue;

    public CThread(List<String> queue) {
        this.queue = queue;
    }

    @Override
    public void run() {
        while (true) {
            synchronized (queue) {
                //如果queue中没有元素,就释放锁,让生产者去生产
                if (queue.size() == 0) {
                    try {
                        queue.wait();  //就释放锁
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                } else {  //消费元素
                    String data = queue.remove(0);
                    System.out.println("消费者线程,消费一个元素:"+data);
                    queue.notify();
                }
            }
        }
    }
}