code: public Map<String, List<String>> parameters() {
      if (params == null) {
        if (hasPath) {
          int pathLength = path().length();
          if (uri.length() == pathLength) {
            return Collections.emptyMap();
          }
          decodeParams(uri.substring(pathLength + 1));
        } else {
          if (uri.isEmpty()) {
            return Collections.emptyMap();
          }
          decodeParams(uri);
        }
      }
      return params;
    }
docs: Returns the decoded key-value parameter pairs of the URI.