Book Image

Learning RxJava - Second Edition

By : Nick Samoylov, Thomas Nield
Book Image

Learning RxJava - Second Edition

By: Nick Samoylov, Thomas Nield

Overview of this book

RxJava is not just a popular library for building asynchronous and event-based applications; it also enables you to create a cleaner and more readable code base. In this book, you’ll cover the core fundamentals of reactive programming and learn how to design and implement reactive libraries and applications. Learning RxJava will help you understand how reactive programming works and guide you in writing your first example in reactive code. You’ll get to grips with the workings of Observable and Subscriber, and see how they are used in different contexts using real-world use cases. The book will also take you through multicasting and caching to help prevent redundant work with multiple Observers. You’ll then learn how to create your own RxJava operators by reusing reactive logic. As you advance, you’ll explore effective tools and libraries to test and debug RxJava code. Finally, you’ll delve into RxAndroid extensions and use Kotlin features to streamline your Android apps. By the end of this book, you'll become proficient in writing reactive code in Java and Kotlin to build concurrent applications, including Android applications.
Table of Contents (22 chapters)
1
Section 1: Foundations of Reactive Programming in Java
5
Section 2: Reactive Operators
12
Section 3: Integration of RxJava applications
Appendix B: Functional Types
Appendix E: Understanding Schedulers

Creating new operators from scratch using lift()

Ideally, you will rarely get to the point where you need to build your own operator from scratch by implementing ObservableOperator or FlowableOperator. ObservableTransformer and FlowableTransformer will hopefully satisfy most cases where you can use existing operators to compose new ones, and this is usually the safest route.

But on occasion, you may find yourself having to do something that the existing operators cannot do or not do easily. After you exhaust all other options, you may have to create an operator that manipulates each onNext(), onComplete(), or onError() event between the upstream and the downstream.

Before you go out and create your own operator, try to use existing operators first with compose() and a transformer. Once that fails, it is recommended that you post a question on StackOverflow and ask the RxJava community...