Java編程題，為按鈕添加事件處理,每按壹次按鈕，數字加5，初始值為0.

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import javax.swing.JButton;

import javax.swing.JFrame;

import javax.swing.JLabel;

public class Adder {

public static void main(String[] args) {

JFrame frame=new JFrame();

frame.getContentPane().setLayout(new FlowLayout());

final JLabel label=new JLabel("0");

frame.getContentPane().add(label);

JButton button=new JButton("按鈕 （+5）");

button.addActionListener(new ActionListener(){

public void actionPerformed(ActionEvent e) {

int current=Integer.parseInt(label.getText());

current+=5;

label.setText(""+current);

}

});

frame.getContentPane().add(button);

frame.setSize(100,150);

frame.setLocationRelativeTo(null);

frame.setVisible(true);

}

}