线程休眠——sleep

package com.thread;

//模拟网络延时：放大问题的发生性
public class TestSleep implements Runnable{

    //票数
    private int ticketNums = 10;
    @Override
    public void run() {
        while(true){
            if(ticketNums<=0){
                break;
            }

            //模拟延时
            try {
                Thread.sleep(200);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

            System.out.println(Thread.currentThread().getName()+"-->拿到了第"+ ticketNums-- +"票");
        }
    }

    public static void main(String[] args) {
        TestSleep testThread = new TestSleep();

        new Thread(testThread,"小明").start();
        new Thread(testThread,"老师").start();
        new Thread(testThread,"黄牛党").start();

    }
}

package com.thread;

//模拟倒计时
public class TestSleep2 {

    public static void tenDown() throws InterruptedException {
        int num = 10;
        while (true) {
            Thread.sleep(1000);
            System.out.println(num--);

            if(num<=0){
                break;
            }
        }

    }


    public static void main(String[] args) {
        try {
            tenDown();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

        //打印当前系统时间
        Date date = new Date(System.currentTimeMillis());   //获取系统当前时间
        while (true){
            try {
                Thread.sleep(1000);
                System.out.println(new SimpleDateFormat("HH:mm:ss").format(date));
                date = new Date(System.currentTimeMillis());   //更新当前时间
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }