Book Image

Learning RxJava

By : Thomas Nield
Book Image

Learning RxJava

By: Thomas Nield

Overview of this book

RxJava is a library for composing asynchronous and event-based programs using Observable sequences for the JVM, allowing developers to build robust applications in less time. Learning RxJava addresses all the fundamentals of reactive programming to help readers write reactive code, as well as teach them an effective approach to designing and implementing reactive libraries and applications. Starting with a brief introduction to reactive programming concepts, there is an overview of Observables and Observers, the core components of RxJava, and how to combine different streams of data and events together. You will also learn simpler ways to achieve concurrency and remain highly performant, with no need for synchronization. Later on, we will leverage backpressure and other strategies to cope with rapidly-producing sources to prevent bottlenecks in your application. After covering custom operators, testing, and debugging, the book dives into hands-on examples using RxJava on Android as well as Kotlin.
Table of Contents (21 chapters)
Title Page
Credits
About the Author
Acknowledgements
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

Custom Transformers and operators for Singles, Maybes, and Completables


There are Transformer and operator counterparts for Single, Maybe, and Completable. When you want to create an Observable or Flowable operator that yields Single, you might find it easier to convert it back into an Observable/Flowable by calling its toObservable() or toFlowable() operators. This also applies to Maybe.

If on some rare occasion you need to create a Transformer or operator specifically to take a Single and transform it into another Single, you will want to use SingleTransformer or SingleOperator. Maybe and Completable will have counterparts with MaybeTransformer/MaybeOperator and CompletableTransformer/CompletableOperator, respectively. The implementation of apply() for all of these should largely be the same experience, and you will use SingleObserver, MaybeObserver, and CompletableObserver to proxy the upstream and downstream.

Here is an example of a SingleTransformer that takes Single<Collection&lt...