public void validaOperadora(KeyEvent e) {
        char c = e.getKeyChar();
        c = (c + "").toLowerCase().charAt(0);
        System.out.println(c);
        if ((c < 'a' || c > 'z') && c != 'ñ' && c != ' ' && c != 'á' && c != 'é' && c != 'í' && c != 'ó' && c != 'ú') {
            e.consume();
        }
    }