myclock.java

java的线程类演示

import java.awt.*;
import java.awt.event.*;
import java.util.*;

public class MyClock implements Runnable
{
	Frame f;
	Label time;
	
	public static void main(String argv[])
	{
		new MyClock();
	}
	
	public MyClock()
	{
		f = new Frame("MyClock");
		f.addWindowListener(new WindowAdapter()
		{
			public void windowClosing(WindowEvent e)
			{
				System.exit(0);
			}
		});
		
		time = new Label(getTime());
		time.setFont(new Font("Arial", Font.PLAIN, 36));
		
		f.add(time, BorderLayout.CENTER);
		f.pack();
		f.setVisible(true);
		
		Thread th = new Thread(this);
		th.start();
	}
	
	public void run()
	{
		while (true)
		{
			try {
				Thread.sleep(1000);
				time.setText(getTime());
			}
			catch (InterruptedException e)
			{
				System.err.println(e);
			}
		}
	}

	private String getTime()
	{
		GregorianCalendar gc = new GregorianCalendar();
		
		return gc.get(GregorianCalendar.HOUR)+":"+
		       gc.get(GregorianCalendar.MINUTE)+":"+
		       gc.get(GregorianCalendar.SECOND);
	}
}