demon

package com.ms;

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

public class TestLuck extends JFrame implements ActionListener {
	/**
	 * 
	 */
	private static final long serialVersionUID = 8003034561463598682L;
	JTextField tf = new JTextField();
	JButton b1 = new JButton("Start");
	JButton b2 = new JButton("Stop");
	boolean isGo = false;

	public TestLuck() {
		b1.setActionCommand("start");
		JPanel p = new JPanel();
		p.add(b1);
		p.add(b2);
		b1.addActionListener(this);
		b2.addActionListener(this);
		b2.setEnabled(false);
		this.getContentPane().add(tf, "North");
		this.getContentPane().add(p, "South");
		this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.setSize(300, 200);
		this.setLocation(300, 300);
		Cursor cu = new Cursor(Cursor.HAND_CURSOR);
		this.setCursor(cu);
		this.setVisible(true);
		tf.setText("welcome you! ");
		this.go();
	}

	public void go() {
		while (true) {
			if (isGo == true) {
				String s = "";
				for (int j = 1; j <= 3; j++) {
					int i = (int) (Math.random() * 10);
					if (i < 10) {
						s = s + " 0" + i;
					} else {
						s = s + " " + i;
					}
				}
				tf.setText(s);
			}
			try {
				Thread.sleep(10);
			} catch (java.lang.InterruptedException e) {
				e.printStackTrace();
			}
		}
	}

	public void actionPerformed(ActionEvent e) {
		String s = e.getActionCommand();
		if (s.equals("start")) {
			isGo = true;
			b1.setEnabled(false);
			b2.setEnabled(true);
		} else {
			isGo = false;
			b2.setEnabled(false);
			b1.setEnabled(true);
		}
	}

	public static void main(String[] args) {
		new TestLuck();
	}
}