Java - Crear botones en Java

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Botones extends JPanel implements java.awt.event.ActionListener
{
JButton b1,b2,b3;

public void actionPerformed(java.awt.event.ActionEvent e)
{
if (e.getActionCommand().equals("disable"))
{
b2.setEnabled(false);
b1.setEnabled(false);
b3.setEnabled(true);
} else
{
b2.setEnabled(true);
b1.setEnabled(true);
b3.setEnabled(false);
}
}
public Botones() {
super();
b1 = new JButton("Deshabilitar");
b1.setVerticalTextPosition(AbstractButton.CENTER);
b1.setHorizontalTextPosition(AbstractButton.LEFT);
b1.setMnemonic('d');
b1.setActionCommand("disable");

b2 = new JButton("Medio");
b2.setVerticalTextPosition(AbstractButton.BOTTOM);
b2.setHorizontalTextPosition(AbstractButton.CENTER);
b2.setMnemonic('m');

b3 = new JButton("Habilitar");
b3.setMnemonic('e');
b3.setActionCommand("enable");
b3.setEnabled(false);

b1.addActionListener(this);
b3.addActionListener(this);

add(b1);
add(b2);
add(b3);
}

public static void main(String[] args) {
JFrame frame = new JFrame("Botones");

frame.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {System.exit(0);}
});

frame.getContentPane().add(new Botones(), BorderLayout.CENTER);
frame.pack();
frame.setVisible(true);
}
}

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