code: private final static byte[] getAlphabet(final int options) {
      if ((options & Base64.URL_SAFE) == Base64.URL_SAFE) {
        return Base64._URL_SAFE_ALPHABET;
      } else if ((options & Base64.ORDERED) == Base64.ORDERED) {
        return Base64._ORDERED_ALPHABET;
      } else {
        return Base64._STANDARD_ALPHABET;
      }
  
    }
docs: Returns one of the _SOMETHING_ALPHABET byte arrays depending on the options specified. It's
  possible, though silly, to specify ORDERED and URLSAFE in which case one of them will be
  picked, though there is no guarantee as to which one will be picked.