常用API

 给当前线程命名

主线程

package com.itheima.d2;

public class ThreadTest1 {
    public static void main(String[] args) {
        Thread t1 = new MyThread("子线程1");
        //t1.setName("子线程1");
        t1.start();
        System.out.println(t1.getName());//获得子线程名字

        Thread t2 = new MyThread("子线程2");
        //t2.setName("子线程2");
        t2.start();
        System.out.println(t2.getName());//获得子线程名字

        //主线程对象的名字
        //哪个线程执行它，它就会得到哪个线程的名字
        Thread m = Thread.currentThread();
        m.setName("主线程");
        System.out.println(m.getName());//获得主线程的名字main

        for (int i = 1; i <= 5; i++) {
            System.out.println(m.getName() + "输出" + i);
        }
    }
}

子线程

package com.itheima.d2;

public class MyThread extends Thread{
    public MyThread(String name){
        super(name);//为当前线程设置名字
    }
    @Override
    public void run() {
        //哪个线程执行它，它就会得到哪个线程的名字
        Thread t = Thread.currentThread();
        for (int i = 1; i <= 5; i++) {
            System.out.println(t.getName() + "输出" + i);
        }
    }
}

join与sleep的用法

package com.itheima.d2;

public class ThreadTest2 {
    public static void main(String[] args) throws Exception {
        for (int i = 1; i <= 5; i++) {
            System.out.println(i);
            //休眠5秒
            if (i == 3){
                //让当前执行的程序暂停5秒，再继续执行
                Thread.sleep(5000);
            }
        }

        //join方法的使用，让当前调用在个方法的线程先执行完
        Thread t1 = new MyThread("子线程1");
        t1.start();
        t1.join();

        Thread t2 = new MyThread("子线程2");
        t2.start();
        t2.join();

        Thread t3 = new MyThread("子线程3");
        t3.start();
        t3.join();
    }
}