code: public static ConfigKeyPath getConfigKeyPath(String input) {
      ConfigKeyPath result = SingleLinkedListConfigKeyPath.ROOT;
      String[] paths = input.split("/");
      for (String p : paths) {
        // in case input start with "/", some elements could be "", which should be skip
        if (p.equals("")) {
          continue;
        }
        result = result.createChild(p);
      }
      return result;
    }
docs: Build the {@link  ConfigKeyPath} based on the absolute/relative path
  @param input - absolute/relative file path
  @return      - {@link  ConfigKeyPath} corresponding to the input