import java.awt.*; 
import java.awt.event.*; 
import javax.swing.*; 

public class TestClock extends JFrame{ 

/** Creates a new instance of TestClock */ 
public TestClock() { 
JPanel jp=new JPanel(); 
final JLabel jl=new JLabel("0"); 

jp.add(jl); 
add(jp,BorderLayout.CENTER); 

JButton jbStart=new JButton("開始"); 
jbStart.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
JButton j =(JButton)e.getSource(); 
j.setEnabled(false); 
dt=new DamThread(new ClockThread(jl)); 
dt.start(); 
} 
}); 

JButton jbPause=new JButton("暫停"); 
jbPause.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
JButton j=(JButton)e.getSource(); 
String s=(String)e.getActionCommand(); 
if(s.equals("暫停")){ 
dt.setStatus(ClockStatus.PAUSE); 
j.setText("繼續"); 
}else{ 
dt.setStatus(ClockStatus.CONTINUE); 
j.setText("暫停"); 
} 
} 
}); 

JButton jbZero=new JButton("清零"); 
jbZero.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
dt.setStatus(ClockStatus.ZERO); 
} 
}); 

JButton jbStop=new JButton("停止"); 
jbStop.addActionListener(new ActionListener() { 
public void actionPerformed(ActionEvent e) { 
dt.setStatus(ClockStatus.STOP); 
} 
}); 

JPanel jp1=new JPanel(); 
jp1.add(jbStart); 
jp1.add(jbPause); 
jp1.add(jbZero); 
jp1.add(jbStop); 
add(jp1,BorderLayout.SOUTH); 
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
pack(); 
setLocationRelativeTo(null); 
} 
public static void main(String[] args) { 
TestClock tc=new TestClock(); 
tc.setVisible(true); 
} 
DamThread dt; 
} 
class DamThread extends Thread{ 
public DamThread(ClockThread c){ 
this.ct=c; 
ct.start(); 
this.setDaemon(true); 
this.STATUS=ClockStatus.START; 
} 
public void run(){ 
while(ct.isAlive()){ 
CheckStatus(); 
} 
} 
private void CheckStatus(){ 
switch(getStatus()){ 
case PAUSE: 
ct.mysuspend(); 
break; 
case ZERO: 
ct.seti(0); 
ct.label.setText("0"); 
setStatus(ClockStatus.START); 
break; 
case STOP: 
ct.seti(1001); 
break; 
case CONTINUE: 
ct.myresume(); 

break; 
default: 
break; 
} 

} 
public void setStatus(ClockStatus cs){ 
this.STATUS=cs; 
} 
public ClockStatus getStatus(){ 
return STATUS; 
} 

ClockStatus STATUS; 
ClockThread ct; 
} 
class ClockThread extends Thread{ 
public ClockThread(JLabel j){ 
this.label=j; 
suspendFlag=false; 
} 
public void run(){ 
while(i<=1000){ 
try { 
i++; 
label.setText(""+i); 
synchronized(this){ 
while(suspendFlag){ 
wait(); 
} 
} 
sleep(100); 
} catch (InterruptedException ex) { 
ex.printStackTrace(); 
} 
} 

} 
public void seti(int in){ 
this.i=in; 
} 

public void mysuspend() 
{ 
suspendFlag=true; 
} 
synchronized void myresume() 
{ 
suspendFlag=false; 
notify(); 
} 
private boolean suspendFlag; 
private int i=0; 
JLabel label; 
} 
enum ClockStatus{ 
START,PAUSE,ZERO,STOP,CONTINUE 
}