生产者消费者

public class Stack {
    char[] a=new char[5];
    int i;
    //压入
    void pull(char s){
        if (i==5) {
            return;
        }
        a[i]=s;
        i++;
    }
    //取出
    char push(){
        if (i==0) {
            return ‘ ‘;
        }
        i--;
        return a[i];
    }
    int size(){
        return i;
    }
}

public class Producer extends Thread{
    private Stack stack;
    public Producer(Stack stack) {
        this.stack=stack;
    }
    @Override
    public void run() {
        while (true) {
            synchronized (stack) {
                while (stack.size()==5) {
                    System.out.println("盘子满了，需等待");
                    try {
                        stack.wait();
                    } catch (InterruptedException e) {
                        System.out.println("盘子满了，需等待");
                    }
                }
                char a = (char) (‘a‘+new Random().nextInt(26));
                stack.pull(a);
                System.out.println("压入数据 : "+a);
                //压入数据后发出通知，盘子里面有数据了
                stack.notifyAll();
            }
        }
    }
}

public class Consumer extends Thread {
    private Stack stack;
    public Consumer(Stack stack) {
        this.stack=stack;
    }
    @Override
    public void run() {
        while (true) {
            synchronized (stack) {
                while (stack.size()==0){
                    System.out.println("盘子里面没有数据，需等待");
                    try {
                        stack.wait();
                    } catch (InterruptedException e) {
                        System.out.println("盘子里面没有数据，需等待");
                    }
                }
                char a = stack.push();
                System.out.println("取出数据 ： "+a);
                //取出数据后发出通知，盘子里面可以放东西了
                stack.notifyAll();
            }
        }
    }
}

public class Test {
    public static void main(String[] args) {
        Stack stack = new Stack();
        Producer producer = new Producer(stack);
        Consumer consumer = new Consumer(stack);
        producer.start();
        consumer.start();

    }
}