code: static Set<String> parsePathParameters(String path) {
          Matcher m = PARAM_URL_REGEX.matcher(path);
          Set<String> patterns = new LinkedHashSet<>();
          while (m.find()) {
              patterns.add(m.group(1));
          }
          return patterns;
      }
docs: Gets the set of unique path parameters used in the given URI. If a parameter is used twice
  in the URI, it will only show up once in the set.