Book Image

Reactive Programming With Java 9

By : Tejaswini Mandar Jog
Book Image

Reactive Programming With Java 9

By: Tejaswini Mandar Jog

Overview of this book

<p>Reactive programming is an asynchronous programming model that helps you tackle the essential complexity that comes with writing such applications.</p> <p>Using Reactive programming to start building applications is not immediately intuitive to a developer who has been writing programs in the imperative paradigm. To tackle the essential complexity, Reactive programming uses declarative and functional paradigms to build programs. This book sets out to make the paradigm shift easy.</p> <p>This book begins by explaining what Reactive programming is, the Reactive manifesto, and the Reactive Streams specifi cation. It uses Java 9 to introduce the declarative and functional paradigm, which is necessary to write programs in the Reactive style. It explains Java 9’s Flow API, an adoption of the Reactive Streams specifi cation. From this point on, it focuses on RxJava 2.0, covering topics such as creating, transforming,fi ltering, combining, and testing Observables. It discusses how to use Java’s popular framework, Spring, to build event-driven, Reactive applications. You will also learn how to implement resiliency patterns using Hystrix. By the end, you will be fully equipped with the tools and techniques needed to implement robust, event-driven, Reactive applications.</p>
Table of Contents (12 chapters)
Free Chapter
1
Introduction to Reactive Programming

Server-side support

Spring 5 supports dealing with Reactive Programming with the addition of a new module named spring-webflux. It uses the Servlet 3.1 non-blocking I/O, which can be run on the Servlet 3.1 container. ServletHttpRequest and ServletHttpResponse expose Flux<DataBuffer> as the request and response body to allow reading and writing of streams. The Spring MVC API is defined in such a way that it is able to support asynchronous and non-blocking I/Os. Spring has the following two modules which add server-side WebFlux support:

  • Annotation based support: The annotations facilitated by Spring Web MVC such as @Controller, @GetMapping, and @PostMapping are now supported to handle reactive types
  • Lambda expression style: Functional Java 8 lambda expression style for routing and handling requests is supported for handling the reactive types
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