多事件监听--java

/*
**********一个事件组可以同时注册多个监听器
**********一个监听器课以同时注册多个事件组
**********事件源的信息可以随他所触发的事件传递到所注册过的监听器
*/
import java.awt.*;
import java.awt.event.*;


public class TestActionEvent2
{
public static void main(String[] args)
{
Frame f = new Frame("MyFrame");
Button b1 = new Button("Start");
Button b2 = new Button("Stop");
Monitor m = new Monitor();
Monitor1 m1 = new Monitor1();
b1.addActionListener(m);
b1.addActionListener(m1);
b2.addActionListener(m);
b2.setActionCommand("Game Over");//设置此按钮激发的动作事件的命令名称。
//在默认情况下，此动作命令设置为与按钮标签相匹配。即是 stop 
f.add(b1,BorderLayout.WEST);
f.add(b2,BorderLayout.CENTER);
f.pack();
f.setVisible(true);
}
}
class Monitor implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
System.out.println("Button Pressed!! return command is :"+e.getActionCommand());
}
}
class Monitor1 implements ActionListener
{
public void actionPerformed (ActionEvent e)
{
System.out.println("HAHA!!!");
}
}