code: public static String decodeKey(String suffixPart) {
      // key is the part *before* KEY_VALUE_DELIMITER
      String key = StringUtils.substringBefore(suffixPart, Character.toString(KEY_VALUE_DELIMITER));
      return UNESCAPE_SPECIAL_CHARS.translate(key);
    }
docs: Decode key
  @param suffixPart Suffix part
  @return Decoded key