Problema com um update simples, como fazer o jButton fazer o update

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

public class Menu extends JFrame implements ActionListener {

  MeuJTextField mjtfCodigo   = new MeuJTextField(20,true);
  MeuJTextField mjtfNome     = new MeuJTextField(20,true);
  MeuJTextField mjtfEndereco = new MeuJTextField(20,false);
  JButton jbOK = new JButton("OK");
  JButton jbCancela = new JButton("Cancelar");
  
  
  Connection con;
  
  public static void main (String args[]) {
     Menu menu = new Menu();

  }
  public Menu() {
     getContentPane().setLayout(new GridLayout(4,4));
     getContentPane().add(new JLabel("Codigo:"));
     getContentPane().add(mjtfCodigo);
     getContentPane().add(new JLabel("Nome:"));
     getContentPane().add(mjtfNome);
     getContentPane().add(new JLabel("Endereco:"));
     getContentPane().add(mjtfEndereco);
     getContentPane().add(jbOK);
     getContentPane().add(jbCancela);
     setSize(300,150);
     setVisible(true);
  }

  public void actionPerformed(ActionEvent e) {
          
      
        try {
            Class.forName("org.firebirdsql.jdbc.FBDriver");
            con = DriverManager.getConnection("jdbc:firebirdsql:localhost:C:\\TESTE.GDB","SYSDBA","masterkey");
            PreparedStatement ps = con.prepareStatement("insert into cliente values(?,?,?)");
            
            ps.setInt(1,Integer.parseInt(mjtfCodigo.getText()));
            ps.setString(2,mjtfNome.getText());
            ps.setString(3,mjtfEndereco.getText());
            
             if (e.getSource() == jbOK){
                ps.executeUpdate();
                JOptionPane.showMessageDialog(this,"Query executada com sucesso");
                
            }
            
             if (e.getSource() == jbCancela){
                
            }
            
            
            
            con.close();
        }
        catch(Exception event){
              JOptionPane.showMessageDialog(null,"Conexão não estabelecida ","Vifique o sistema",JOptionPane.ERROR_MESSAGE);
         }
      



 }


class MeuJTextField extends JTextField implements FocusListener {

  private boolean obrigatorio = false;

  public MeuJTextField(int tamanho, boolean obrigatorio) {
     super(tamanho);
     this.obrigatorio = obrigatorio;
     if (obrigatorio)
        setBackground(Color.yellow);
      else
        setBackground(Color.white);
     addFocusListener(this);
  }

  public void focusGained(FocusEvent e) {
     setBackground(Color.orange);
  }

  public void focusLost(FocusEvent e) {
     if (obrigatorio)
        setBackground(Color.yellow);
      else
        setBackground(Color.white);
  }
}

class MeuPainelComboBox extends JPanel {

  private JComboBox jcb = new JComboBox();


  public MeuPainelComboBox() {
     super();
     setLayout(new GridLayout(1,2));
     add(jcb);
     
  }
}
}