编写程序，实现如图所示功能：在宽高文本框中输入数值，当单击“更改”按钮时，将窗体大小改为文本框中输入值，单击“退出”时，退出应用程序。

贴一个代码，随便写的，不过能运行：）

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class LabelPanel extends JPanel {

 JTextField width, hight;
 LabelPanel() {
  add(new JLabel(\"宽\"));
  width = new JTextField(10);
  add(width);
  add(new JLabel(\"高\"));
  hight = new JTextField(10);
  add(hight);

 }
}
class MyFrame extends JFrame {

 private LabelPanel panel = new LabelPanel();

 

 public MyFrame() {
  setTitle(\"窗口大小\");
  setSize(300, 200);
  Container contentPane = getContentPane();
  contentPane.add(panel, BorderLayout.CENTER);
  contentPane.add(new ButtonPanel(), BorderLayout.SOUTH);

 }

 

 private class ButtonPanel extends JPanel
   implements ActionListener {
  JButton modify = new JButton(\"更改\");
  JButton quit = new JButton(\"退出\");
  
  public ButtonPanel() {
   modify.addActionListener(this);
   quit.addActionListener(this);
   add(modify);
   add(quit);
  }
  public void actionPerformed(ActionEvent e) {
   Object source = e.getSource();
   if(source == modify) {
    String width = panel.width.getText();
    String hight = panel.hight.getText();
    if(width.equals(\"\") || hight.equals(\"\"))
     JOptionPane.showMessageDialog(MyFrame.this,
       \"Please enter the data!\");
    else {
     int w = Integer.parseInt(width);
     int h = Integer.parseInt(hight);
     
     MyFrame.this.setSize(w, h);
    }
   } else if(source == quit) {
    System.exit(0);
   }
  }

 }
}
public class EventTest {

 public static void main(String[] args) {
  MyFrame test = new MyFrame();
  test.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
  test.show();

 }
}