Java的小项目 秒表

 想关的代码如下：

请高手来指教的

 

package Cn.hnpi;

import java.awt.Color;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Date;

import javax.swing.*;

public class Clock {

 public static void main(String[] args) {
  
  JFrame jf = new JFrame("计数器");
  JButton pause = new JButton("Pause");
  JLabel clock = new JLabel("Timer");
  
  clock.setBackground(Color.GREEN);
  clock.setOpaque(true);
  clock.setHorizontalAlignment(JLabel.CENTER);
  jf.add(clock,"Center");
  jf.add(pause,"North");
  jf.setSize(140,80);
  jf.setLocation(500,300);
  jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  jf.setVisible(true);
  
  MyThread mt = new MyThread(clock,100000);
  mt.start();
  MyListener ml = new MyListener(clock,mt);
  pause.addActionListener(ml);
 }
}

class MyThread extends Thread{
 private JLabel clock;
 private long time;
 private long end;
 
 public MyThread(JLabel clock, long time){
  this.clock = clock;
  this.time = time;
 }
 
 public void init(){
  long start = new Date().getTime();
  end = start + time;
 }
 
 public void run(){
  init();
  while(true){
   long now = new Date().getTime();
   time = end - now;
   if(time > 0){
    String s = this.convert(time);
    clock.setText(s);
   }else{
    break;
   }
   try{
    Thread.sleep(10);
   }catch(InterruptedException e){
    e.printStackTrace();
   }
  }
  clock.setText("时间到！");
  clock.setBackground(Color.RED);
 }
 
 public String convert(long time){
  long h = time / 3600000;
  long m = (time % 3600000) / 60000;
  long s = (time % 60000) / 1000;
  long ms = (time % 1000) / 10;
  
  String ph = h<10 ? "0" : "";
  String pm = m<10 ? "0" : "";
  String ps = s<10 ? "0" : "";
  String pms = ms<10 ? "0" : "";
  
  String txt = ph + h + ":" + pm + m + ":" + ps + s + "." + pms + ms;
  return txt;
 }
}

class MyListener implements ActionListener{
 private JLabel clock;
 private MyThread mt;
 private boolean running = true;
 
 public MyListener(JLabel clock, MyThread mt){
  this.clock = clock;
  this.mt = mt;
 }
 
 public void actionPerformed(ActionEvent e){
  if(!mt.isAlive()){
   return;
  }
  JButton jb = (JButton) e.getSource();
  if(running){
   jb.setText("Replay");
   clock.setBackground(Color.YELLOW);
   mt.suspend();
  }else{
   jb.setText("Pause");
   clock.setBackground(Color.GREEN);
   mt.init();
   mt.resume();
  }
  running = !running;
 }
}