Esercizio “auguri”

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class Benvenuto {
JFrame f1= new JFrame("Benvenuto");
JFrame f2=new JFrame();
JTextField t1=new JTextField();
JButton b1=new JButton("vai!");
JLabel l1=new JLabel();
JLabel l2=new JLabel();

public void apriFinestra(){
    f1.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f1.add(BorderLayout.NORTH,t1);
    b1.addActionListener(new Bottone());
    f1.add(BorderLayout.SOUTH,b1);
    f1.setSize(200,100);
    f1.setVisible(true);
}
class Bottone implements ActionListener{
    public void actionPerformed(ActionEvent e){
        String nome=t1.getText();
        l1.setText(nome+" Auguri!");
        f2.add(BorderLayout.CENTER,l1);
        f2.pack();
        f2.setVisible(true);
    }
}
public static void main(String Args[]){
    Benvenuto b=new Benvenuto();
    b.apriFinestra();
}
}