validação de CPF

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


public class CPF extends JFrame
{
  private JButton botao;
  private JTextField field;

  public CPF()
  {
    super("CPF");

    getContentPane().setLayout(new FlowLayout());

    field = new JTextField(10);
    field.setEditable(false);
    getContentPane().add(field);

    botao = new JButton("Gerar");
    getContentPane().add(botao);
    botao.setFocusPainted(false);
    botao.addActionListener(new ActionHandler());

    addWindowListener(new WindowHandler());

    setSize(300,300);
    pack();
    show();
    setResizable(false);
  }

  public static void main(String args[])
  {
    new CPF();
  }

  private class ActionHandler implements ActionListener
  {
    public void actionPerformed(ActionEvent e)
    {
      int vet[] = new int[11];
      byte i = 0;
      byte j = 0;
      int total = 0;

      for (i = 0, j = 10; i < 9; i++, j--)
      {
        vet[i] = (byte)(Math.random() * 10);
        total += (vet[i] * j);
      }

      int num = 11 - (total % 11);
      vet[9] = (num < 10 ? num : 0);

      total = 0;

      for (i = 0, j = 11; i <= 10; i++, j--)
        total += (vet[i] * j);

      num = 11 - (total % 11);

      vet[10] = (num < 10 ? num : 0);

      String cpf = "";

      for (i = 0; i < vet.length; i++)
      {
        cpf += vet[i] + "";

        if ((i == 2) || (i == 5))
          cpf += ".";
        else
          if (i == 8)
            cpf += "-";
      }

      field.setText(cpf);
    }
  }

  private class WindowHandler extends WindowAdapter
  {
    public void windowClosing(WindowEvent e)
    {
      System.exit(0);
    }
  }
}

valeu aos colegas q já tentaram ajudar !