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

Queue-based load leveling pattern

The queue will work as a buffer between the task and the service it invokes. As a queue acts as a buffer, it facilitates handling the load that may occur at peak demands, leading to the failure of the service.

The application keeps on serving enormous requests continuously coming from consumers. Whenever the application has few requests, it serves each request successfully. While, at peak hours, when more requests hit the service due to increase in the load, the service may face reliability issues.

Some of the services in the application use common resources concurrently. The volume of the request is not predictable, and may ultimately cause failure due to an increase in the load.

The increase in the load can be managed by introducing the queue in between the task and the queue. The task and the services run asynchronously, where the task posts...