Have you ever wanted to perform multiple HTTP requests in Java in parallel and wondered how to execute them in a non blocking fashion ? In this post we are going to explain how to execute them using a nonblocking RESTful API controller using the Spring WebFlux (Netty) framework with WebClient, based on Project Reactor Nonblocking REST controller It is necessary to use the Flux<> type to signify there is a list of items in the response Spring Webflux Client In our example, the Spring Webflux client returns a single string which represents an XML value. It uses a reactive stream using the Mono<> type. Its value is mapped to an object using Jackson. The three HTTP calls are then merged using the Flux.merge statement Performance Comparison The link below compares the performance of API requests performed using the Spring Webflux framework with WebClient versus DeferredResult or CompletableFuture with Servlet and a Blocking HTTP call with servlet https:/...