code: public static HttpStatusException of(int statusCode) {
          if (statusCode < 0 || statusCode >= 1000) {
              final HttpStatus status = HttpStatus.valueOf(statusCode);
              if (Flags.verboseExceptions()) {
                  return new HttpStatusException(status);
              } else {
                  return new HttpStatusException(status, false);
              }
          } else {
              return EXCEPTIONS[statusCode];
          }
      }
docs: Returns a new {@link HttpStatusException} instance with the specified HTTP status code.