public class Product {

    private MyStack myStack;

    public Product(MyStack myStack) {

        this.myStack = myStack;

    }

    public void pushService(){

        myStack.push();

    }

}

public class Consumer {

    private MyStack myStack;

    public Consumer(MyStack myStack) {

        this.myStack = myStack;

    }

    public void popService(){

        myStack.pop();

    }

}

public class ThreadP extends Thread {

    private Product product;

    public ThreadP(Product product) {

        this.product = product;

    }

    @Override

    public void run() {

        while (true) {

            product.pushService();

        }

    }

}

public class ThreadC extends Thread{

    private Consumer consumer;

    public ThreadC(Consumer consumer) {

        this.consumer = consumer;

    }

    @Override

    public void run() {

        while (true) {

            consumer.popService();

        }

    }

}

public class MyStack {

    private List list = new ArrayList<>();

    synchronized public void push() {

        try {

            while (list.size() == 1) {

                this.wait();

            }

            list.add("anything=" + Math.random());

            this.notifyAll();

            System.out.println("push=" + list.size());

        } catch (InterruptedException e) {

            e.printStackTrace();

        }

    }

    synchronized public String pop() {

        String returnValue = "";

        try {

            while (list.size() == 0) {

                System.out.println("pop wait begin"+Thread.currentThread().getName());

                this.wait();

            }

            returnValue = "" + list.size();

            list.remove(0);

            Thread.sleep(1000);

            this.notifyAll();

            System.out.println("pop end"+list.size());

        } catch (InterruptedException e) {

            e.printStackTrace();

        }

        return returnValue;

    }

}

/**

 * Created by wangbin10 on 2018/7/10.

 * 多生产多消费的情况程序运行后出现假死：

 * 原因是虽然代码中已经wait/notify进行通信了，但是不能保证notify唤醒的就是是同类还是异类

 * 可能会出现生产者唤醒生产者，消费者唤醒消费者的情况，长此以往，所有线程都进行等待

 * 解决的办法就是将notify换成notifyAll

 */

public class Test {

    public static void main(String[] args) {

        MyStack myStack=new MyStack();

        Product p1 = new Product(myStack);

        Product p2 = new Product(myStack);

        Product p3 = new Product(myStack);

        Product p4 = new Product(myStack);

        ThreadP tp1=new ThreadP(p1);

        ThreadP tp2=new ThreadP(p2);

        ThreadP tp3=new ThreadP(p3);

        ThreadP tp4=new ThreadP(p4);

        tp1.start();

        tp2.start();

        tp3.start();

        tp4.start();

        Consumer c1 = new Consumer(myStack);

        Consumer c2 = new Consumer(myStack);

        Consumer c3 = new Consumer(myStack);

        Consumer c4 = new Consumer(myStack);

        ThreadC tc1 = new ThreadC(c1);

        ThreadC tc2 = new ThreadC(c2);

        ThreadC tc3 = new ThreadC(c3);

        ThreadC tc4 = new ThreadC(c4);

        tc1.start();

        tc2.start();

        tc3.start();

        tc4.start();

    }

}