return createSizedJTextField(len, numbersOnly, false);
return new JTextField(numbersOnly ? new NumericMaxLengthDocument(len, hex ? "[^0-9a-fA-F]" : null) : new MaxLengthDocument(len), "", len);
    public static JTextField createSizedJTextField(int len, boolean numbersOnly)    {        return createSizedJTextField(len, numbersOnly, false);    }