} else {
          throw new DecodingException("Unrecognized character: " + ch);
        }
      }
      return result;
    }

    private boolean hasLowerCase() {
      for (char c : chars) {
        if (Ascii.isLowerCase(c)) {
          return true;
        }
      }
      return false;
    }

    private boolean hasUpperCase() {