老师发作业继承Thread

package com.heima.lei;public class Test8 {    /**老师发作业继承Thread     * @param args     */    public static void main(String[] args) {        Thread t1 = new MyThread();        Thread t2 = new MyThread();        Thread t3 = new MyThread();        Thread t4 = new MyThread();        t1.setName("第一位老师：");        t2.setName("第二位老师：");        t3.setName("第三位老师：");        t4.setName("第四位老师：");        t1.start();        t2.start();        t3.start();        t4.start();    }}class MyThread extends Thread{    private static int books = 100;    public void run() {        while(true){            synchronized (MyThread.class) {                if(books == 0){                    break;                }                try {                    Thread.sleep(10);                } catch (InterruptedException e) {                    e.printStackTrace();                }                System.out.println(getName()+"第"+books-- + "本书！");            }        }    }}