new Thread(new Runnable() {

            public void run() {

                while (true) {

                    test();

                    try {

                        Thread.sleep(500);

                    } catch (InterruptedException e) {

                        // TODO Auto-generated catch block

                        e.printStackTrace();

                    }

                }

            }

            private void test() {

                // TODO Auto-generated method stub

            }

            public Runnable start() {

                // TODO Auto-generated method stub

                return null;

            }

        }.start());

import java.awt.Robot;

import java.util.Date;

public class test {

     public   static   void   main(String[]   args)   throws   Exception{

         Robot  r   =   new   Robot();

         System.out.println( "延时前:"+new Date().toString()  );

         r.delay(   2000   );

         System.out.println(   "延时后:"+new Date().toString()   );

   }

}

import java.util.*;

public class test {

    public static void main(String[] args) {

        Timer timer = new Timer();// 实例化Timer类

        timer.schedule(new TimerTask() {

            public void run() {

                System.out.println("退出");

                this.cancel();

            }

        }, 5000);// 这里百毫秒

        System.out.println("本程序存在5秒后自动退出");

    }

}