runnablethread.java

模拟时钟和数字时钟

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


//通过Runnable接口定义线程类
public class RunnableThread extends JApplet implements Runnable
{
	Thread clockThread;
	public void start()
	{
		if (clockThread==null)
		{
			clockThread=new Thread(this,"Clock");
			clockThread.start();
		}
	}
	
	public void run()
	{
		while(clockThread!=null)
		{
			repaint();//实际上是显示一个时钟
			try
			{
				clockThread.sleep(1000);
			}catch(InterruptedException e) {}
		}
	}


public void paint(Graphics g)
{
	super.paint(g);
	Calendar now = GregorianCalendar.getInstance();
	g.drawString(now.get(Calendar.HOUR)+":"+now.get(Calendar.MINUTE)+":"+now.get(Calendar.SECOND),5,10);
	
}

public void stop()
{
	clockThread = null;
	clockThread=null;
}


}