ProducerConsumerDemo.java

public class ProducerConsumerDemo{
    public static void main(String[] args){
        Resource r = new Resource();
        Producer pro = new Producer(r);
        Consumer con = new Consumer(r);

        Thread t1 = new Thread(pro);
        Thread t2 = new Thread(pro);
        Thread t3 = new Thread(con);
        Thread t4 = new Thread(con);

        t1.start();
        t2.start();
        t3.start();
        t4.start();
    }
}



class Resource{
    private String name;
    private int count = 1;
    private boolean flag = false;

    public synchronized void set(String name){
        while(flag)
            try{this.wait();}catch(Exception e){}
        this.name = name + "--"+count++;
        System.out.println(Thread.currentThread().getName() + "...P......."+this.name);
        flag = true;
        this.notifyAll();
    }

    public synchronized void out(){
        while(!flag)
            try{this.wait();}catch(Exception e){}
        System.out.println(Thread.currentThread().getName() + "...C.."+this.name);
        flag = false;
        this.notifyAll();
    }
}


class Producer implements Runnable{
    private Resource res;
    Producer(Resource res){
        this.res = res;
    }

    public void run(){
        while(true){
            res.set("+Goods+");
        }
    }
}

class Consumer implements Runnable{
    private Resource res;
    Consumer(Resource res){
        this.res = res;
    }

    public void run(){
        while(true){
            res.out();
        }
    }
}