JAVA編程題:創建有壹個文本框和三個按鈕的小程序。當按下每個按鈕時，使不同的文字顯示在文本框中

import javax.swing.JFrame;

import javax.swing.JButton;

import javax.swing.JTextField;

import java.awt.FlowLayout;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.awt.event.WindowAdapter;

import java.awt.event.WindowEvent;

public class Test extends JFrame implements ActionListener{

private static final long serialVersionUID = 1L;

private JPanel jPanel;

private JButton jButton1,jButton2,jButton3;

private JTextField tf1;

public Test(String title) {

super(title);

init();

}

private void init() {

jPanel=new JPanel();

jPanel.setLayout(new FlowLayout());

tf1=new JTextField(20);

jButton1=new JButton("按鈕1");

jButton2=new JButton("按鈕2");

jButton3=new JButton("按鈕3");

jButton1.addActionListener(this);

jButton2.addActionListener(this);

jButton3.addActionListener(this);

jPanel.add(tf1);

jPanel.add(jButton1);

jPanel.add(jButton2);

jPanel.add(jButton3);

this.add(jPanel);

this.setSize(300,100);

this.setResizable(false);

this.setVisible(true);

this.addWindowListener(new WindowAdapter() {

public void windowClosing(final WindowEvent e) {

System.exit(0);

}

});

}

public void actionPerformed(ActionEvent e) {

if(e.getSource().equals(jButton1)){

tf1.setText("按鈕1");

}

if(e.getSource().equals(jButton2)){

tf1.setText("按鈕2");

}

if(e.getSource().equals(jButton3)){

tf1.setText("按鈕3");

}

}

public static void main(String[] args){

new Test("文字變換");

}

}