import javax.swing.*;import java.awt.event.*;import java.awt.*;
public class ActionThree extends JFrame...{
public static void main(String[] args) ...{
new ActionThree();
} JButton b,b1; public ActionThree() ...{ super("action first"); //JPanel p=new JPanel(); this.setLayout(new FlowLayout()); b=new JButton("click"); b1=new JButton("reClick"); this.getContentPane().add(b); this.getContentPane().add(b1); b.addActionListener(new action());//注册监听 b1.addActionListener(new action()); this.setSize(300,300); this.setVisible(true); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); } class action implements ActionListener...{ public void actionPerformed(ActionEvent e)...{ /**//*if(e.getActionCommand().equals("click")) { JOptionPane.showMessageDialog(ActionThree.this,"小子，你又错了，最后一次了！！"); //静态方法。不用声明 } else JOptionPane.showMessageDialog(ActionThree.this,"123456789");*/ JButton jb=(JButton)e.getSource(); if(jb==b) JOptionPane.showMessageDialog(ActionThree.this,"小子，你又错了，最后一次了！！"); else JOptionPane.showMessageDialog(ActionThree.this,"123456789"); } } 
}