🚀 go-pugleaf

I wrote follow codes,and found this thread only run once
I hope this thread run twice,and i think the program will print:
Thread is running
Thread exit
Thread is running
Thread exit

In fact ,it is :
Thread is running
Thread exit




public class ThreadTest2 {
    MyThread mythread;
    /** Creates a new instance of ThreadTest2 */
    public ThreadTest2() {
        mythread = new MyThread();
        test();
    }
    
    private void test() {
        mythread.start();
        try {
            Thread.sleep(1000l);// mythread has finish his job
        }
        catch(Exception ex) {
            ex.printStackTrace();
        }        
        mythread.start();
    }
    
    /**
     * test main method
     */
    static public void main(String[] args) {
        ThreadTest2 test = new ThreadTest2();
    }
}

class MyThread extends Thread {
    public MyThread() {
        
    }
    
    public void run() {
        System.out.println("Thread is running");
        System.out.println("Thread exit");
    }
}