foldSample.java

//Acceptance validation on the range of data being requested
acceptableInterval(from, to, DeviceParameters.from(paramId).getResolution())
    .fold(
        failure -> asyncResponse
                             .resume(status(422)
                             .entity(asErrorReply(failure))
                             .build())
        ,

        accepted -> runAsync(() -> {

          final OptionalLong deployment = activeDeploymentFrom(request);

          if (deployment.isPresent()) {

            log.info("Active deployment found within request: {}", deployment.getAsLong());

            FetchCriteria criteria = ... //Some fetching criteria is created

            readings
                .fetch(criteria)
                .thenApplyAsync(outcome -> replyWith(outcome.mapR(asApiReadings), asyncResponse), executor)
                .exceptionally(asyncResponse::resume);

          } else {
            log.warn("No active deployment nor subject was found within request");
          }