笔记20200512:多线程【并发问题】

案例:多个线程同时操做同一个对象:买火车票的例子【多线程操做不安全咋处理呢?】
package com.chengguo.线程;

/**
 * 多个线程同时操做同一个对象:买火车票的例子【多线程操做不安全咋处理呢?】
 */
public class Demo_20200509002_Thread implements Runnable {
    //定义火车票默认张数
    private int ticketNums = 10;

    @Override
    public void run() {
        while (true) {
            if (ticketNums <= 0) {
                break;
            } else {

                try {
                    //模拟延时
                    Thread.sleep(4000);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }

                //获取当前票的名字:Thread.currentThread().getName();每抢一张票就--
                System.out.println(Thread.currentThread().getName() + "拿到了第" + ticketNums-- + "张票");
            }

        }

    }

    public static void main(String[] args) {
        //建立runnable接口的实现类对象
        Demo_20200509002_Thread dt1 = new Demo_20200509002_Thread();
        //建立一个线程对象,经过线程对象来开启线程
        new Thread(dt1,"A").start();
        new Thread(dt1,"B").start();
        new Thread(dt1,"C").start();
    }
}