41. wait notify 方法

//生产者  消费者   商品,生产一个，就消费一个

//产品
class Product{
    String name;
    double price;
    boolean flag = false;//判断是否生产完的标志
}

//生产者
class Producer implements Runnable{
    Product p;
    
    public Producer(Product p) {
        this.p = p;
    }
    @Override
    public void run() {
        int i = 0;
        while(true) {
            synchronized (p) {
                if(p.flag == false) {
                    if(i%2 == 0) {
                        p.name = "香蕉";
                        p.price = 2.0;
                    }else {
                        p.name = "苹果";
                        p.price = 6.5;
                    }
                    System.out.println("生产了"+p.name+"价格"+p.price);
                    i++;
                    p.flag = true;//生产完了
                    p.notify();//唤醒消费者消费
                    p.notifyAll();
                }else {
                    try {
                        p.wait();//产品生产完了等待消费者去消费
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
            }
        }
        
    }
}
//消费者
class Customer implements Runnable{
    Product p;
    
    public Customer(Product p) {
        this.p = p;
    }
    @Override
    public void run() {
        while(true) {
            synchronized (p) {
                if(p.flag == true) {
                    System.out.println("消费者消费了"+p.name+"花费"+p.price);
                    p.flag = false;
                    p.notify();//唤醒生产者生产
                }else {
                    try {
                        p.wait();//消费完了，等待生产者去生产
                    } catch (InterruptedException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }
            }
        }
        
    }
}
public class Demo9 {
    public static void main(String[] args) {
        Product p = new Product();
        Producer producer = new Producer(p);
        Customer customer = new Customer(p);
        Thread thread1 = new Thread(producer,"生产者");
        Thread thread2 = new Thread(customer,"消费者");
        thread1.start();
        thread2.start();
    }
}