线程相关

实现线程的两种方式：

继承Thread或实现Runnable接口

线程的生命周期：

多个线程操作同一数据的安全用例：

import org.junit.Test;

import java.util.concurrent.CountDownLatch;

//多个线程下对ticket的售卖
public class TestThread {

    @Test
    public void ssss() {
        int threadNum = 4;
        //@Test不同于main方法，需要下面的同步工具等待子线程执行完成
        //启用同步工具类对子线程计数，为了让主线程启动子线程后，等待子线程完成对应的工作
        CountDownLatch countDownLatch = new CountDownLatch(threadNum);
        //开启子线程,为了让他们的锁一致，多个线程需要同一个对象
        MyTask myTask = new MyTask(countDownLatch);
        for (int i = 0; i < threadNum; i++) {
            new Thread(myTask).start();
        }

        try {
            countDownLatch.await();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

class MyTask implements Runnable {
    private CountDownLatch countDownLatch;
    private int ticket = 100;

    public MyTask(CountDownLatch countDownLatch) {
        this.countDownLatch = countDownLatch;
    }

    @Override
    public void run() {
        while (ticket>0){
            sale();
            try {
                Thread.currentThread().sleep(500);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        countDownLatch.countDown();
    }

    public void sale() {
        synchronized (MyTask.class) {
            System.out.println(Thread.currentThread().getName() + "::::::::出售第" + ticket--);
        }
    }
}