关于线程的等待（基础）（练习）

public class BoxDemo {
    public static void main(String[] args) {
        Box b = new Box();
        Producer p = new Producer(b);
        Customer c = new Customer(b);
        Thread t1 = new Thread(p);
        Thread t2 = new Thread(c);
        t1.start();
        t2.start();
    }
}

public class Producer implements Runnable{
    //生产者类
    private Box b;
    public Producer(Box b) {
        this.b = b;
    }

    @Override
    public void run() {
        for (int i = 1; i <= 10; i++) {
            b.put(i);
        }
    }
}

public class Customer implements Runnable{
    //取奶类
    private Box b;

    public Customer(Box b) {
        this.b = b;
    }

    @Override
    public void run() {
        while (true){
            b.get();
        }
    }
}

public class Box {
    //奶箱类
    private int milk;
    //表示奶箱状态的变量
    private boolean state = false;

    public synchronized void put(int milk) {
        if (state){
            try {
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        this.milk = milk;
        System.out.println("送奶工将第" + this.milk + "瓶奶放入奶箱");
        state = true;
        notifyAll();
    }

    public synchronized void get() {
        if (!state){
            try {
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        System.out.println("用户拿到第" + this.milk + "瓶奶");
        state = false;
        notifyAll();
    }
}