code: static Response<Integer> add(Request request) {
      Optional<String> t1 = request.parameter("t1");
      Optional<String> t2 = request.parameter("t2");
      if (t1.isPresent() && t2.isPresent()) {
        int result = Integer.valueOf(t1.get()) + Integer.valueOf(t2.get());
        return Response.forPayload(result);
      } else {
        return Response.forStatus(Status.BAD_REQUEST);
      }
    }
docs: A simple adder of request parameters {@code t1} and {@code t2}
  
  @param request  The request to handle the addition for
  @return A response of an integer representing the sum