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！");
            }
        }
    }
}