Thread操作

1. 启动两个线程

public class ThreadTest {

    public static boolean isRun = false;
    
    @Test
    public void mainTest(){
        System.out.println(Thread.currentThread().getName());
        
        Thread readThread = new ReadThread();
        readThread.setName("readThread");
        
        Thread writeThread = new WriteThread();
        writeThread.setName("writeThread");
        
        readThread.start();
        writeThread.start();
    }
}

class ReadThread extends Thread{
    @Override
    public void run() {
        try {
            // 读操作比较耗时，消耗3秒的时间
            // 由于主线程很肯能已经结束，所以，这个方法有可能不会执行到
            sleep(3000);
            System.out.println(Thread.currentThread().getName());
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

class WriteThread extends Thread{
    @Override
    public void run() {
        System.out.println(Thread.currentThread().getName());
    }
}

2. 由于上面的 readThread 线程比较耗时(sleep模拟)，所以常常会发生主线程执行完毕，而 readThread 却没有被执行的情况，下面就想办法使得主线程等待 readThread

线程执行完毕：