code: public static boolean isTransmittable(int statusCode) {
          return (statusCode == NORMAL) ||
                  (statusCode == SHUTDOWN) ||
                  (statusCode == PROTOCOL) ||
                  (statusCode == BAD_DATA) ||
                  (statusCode == BAD_PAYLOAD) ||
                  (statusCode == POLICY_VIOLATION) ||
                  (statusCode == MESSAGE_TOO_LARGE) ||
                  (statusCode == REQUIRED_EXTENSION) ||
                  (statusCode == SERVER_ERROR) ||
                  (statusCode == SERVICE_RESTART) ||
                  (statusCode == TRY_AGAIN_LATER) ||
                  (statusCode == INVALID_UPSTREAM_RESPONSE);
      }
docs: Test if provided status code can be sent/received on a WebSocket close.
  <p>
  This honors the RFC6455 rules and IANA rules.
  </p>
  
  @param statusCode the statusCode to test
  @return true if transmittable