多线程--生产者/消费者

/**
 * Created by Administrator on 2017/6/26.
 * 生产者/消费者问题
 * 生产者(Producer)将产品交给店员(Clerk)，而消费者(Customer)从店员处取走产品，
 * 店员一次只能持有固定数量的产品，如果生产者试图生产更多的产品，
 * 店员会叫生产者停一下，如果店中有空位放产品了再通知生产者继续生产；
 * 如果店中没有产品了，店员会告诉消费者等一下，如果店中有产品了再通知消费者来取走产品。
 */
public class TestProduct {
    public static void main(String[] args) {
        Clerk clerk = new Clerk();
        Producer p1 = new Producer(clerk);
        Thread t1 = new Thread(p1);
        Thread t2 = new Thread(p1);

        Customer c1 = new Customer(clerk);
        Thread t3 = new Thread(c1);

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

/**
 * 生产者类
 */
class Producer implements Runnable{
    Clerk clerk;
    public Producer(Clerk clerk){ this.clerk=clerk; }
    @Override
    public void run() {
        System.out.println("生产产品");
        while (true){
            try {
                Thread.sleep((int)(Math.random() * 1000));
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            clerk.addProduct();
        }
    }
}

/**
 * 消费者类
 */
class Customer implements Runnable{
    Clerk clerk;
    public Customer(Clerk clerk){ this.clerk=clerk;}

    @Override
    public void run() {
        System.out.println("消费产品");
        while (true){
            try {
                Thread.sleep((int)(Math.random() * 1000));
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            clerk.consumeProduct();
        }
    }
}

/**
 * 店员类
 */
class Clerk{
    int product;
    public synchronized void consumeProduct(){
        if(product<=0){
            try {
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }else{
            System.out.println(Thread.currentThread().getName()+":消费 "+product);
            product--;
            notifyAll();
        }
    }
    public synchronized void addProduct(){
        if(product>=20){
            try {
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }else{
            product++;
            System.out.println(Thread.currentThread().getName()+": 生产 "+product);
            notifyAll();
        }
    }
}