各位大侠帮我看看这个界面到底出了什么问题，怎么就是改不出来！

import java.awt.*;
import java.awt.event.*;
public class MenuTest
{
public static void main(String[]args)
{
MenuFrame form=new MenuFrame();
form.setVisible(true);
}
}
class MenuFrame extends Frame implements ActionListener
{
TextFiled t1=new TextFiled(15);
TextFiled t2=new TextFiled(15);
Label lb1=new Label("用户名");
Label lb2=new Label("密码");
Button b1=new Button("确定");
//super("学生管理系统登录");
public void init()
{
add(t1);
add(t2);
add(b1);
add(lb1);
add(lb2);
setSize(300,300);
addWindowListener(new Tuichu());
b1.addActionListener(this);
}
public void adtionPerformed(ActionEvent e)
{
lb1.setText(e.getActionCommand());
lb2.setText(e.getActionCommand());
}
}
class Tuichu extends WindowAdapter
{
public void WindowClosing(WindowEvent e)
{
System.exit(0);
}
}

谢谢斑竹，真是好人，真细心！