Java上机

package test;
import javax.swing.*;
import java.awt.Event;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
public class SwingTest implements ActionListener{
     JFrame f;
     JPanel p;
     JLabel l1;
     JLabel l2;
     JTextField t;
     JPasswordField jp;
     JButton b;
     public SwingTest(){
    	 f = new JFrame();
    	 p = new JPanel();
    	 l1 = new JLabel("账号");
    	 l2 = new JLabel("密码");
    	 t = new JTextField(10);
    	 b = new JButton("登录");
    	 b.addActionListener(this);
    	 jp = new JPasswordField(10);
    	 p.add(l1);
    	 p.add(t);
    	 p.add(l2);
    	 p.add(jp);
    	 p.add(b);
    	 f.add(p);
    	 f.setVisible(true);
    	 f.setSize(400,300);
     }
     public static void main(String[] args) {
    	 new SwingTest();
     }
	@Override
	public void actionPerformed(ActionEvent e) {
		JFrame f2 = new JFrame(); 
		JPanel p2 = new JPanel();
		JButton b2 = new JButton("注册");
		JLabel l3 = new JLabel("该账号未注册！");
		p2.add(l3);
		p2.add(b2);
		f2.add(p2);
		f2.setVisible(true);
		f2.setSize(400,300);
	}
}