multithreaddemo3.java

java程序设计语言源代码

//Example 3 of Chapter 8

import java.awt.*;
import javax.swing.*;
import java.applet.Applet;
import java.util.Date;

public class MultiThreadDemo3 extends Applet implements Runnable
{
	Thread clockThread;
	
	public  void  start()
	{
		if(clockThread==null)
		{
			clockThread = new Thread( this, "Clock" );
			clockThread.start();
		}
	}
	
	public void run()
	{
		while(clockThread!=null)
		{
			repaint();
			try{
				clockThread.sleep(1000);
			}
			catch ( InterruptedException exception )
			{
				exception.printStackTrace();
			}
		}
	}
	
	public void paint( Graphics g )
	{
		Date now = new Date();
		g.setFont( new Font( "Dialog", Font.PLAIN, 60 ) );
		g.drawString( now.getHours() + ":" + now.getMinutes() +
			":" + now.getSeconds() , 5 , 80);
	}
	
	public void stop()
	{
		clockThread.stop();
		clockThread = null;
	}
}