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

Summary


In this chapter, we got our feet wet by creating our own operators. It is preferable to use ObservableTransformer and FlowableTransformer to compose existing operators together to create new ones, and even with that, you need to be cautious when introducing stateful resources that cause undesirable side-effects. When all else fails, you can create your own ObservableOperator or FlowableOperator and create an operator at a low level that intercepts and relays each emission and event. This can be tricky and you should exhaust all other options, but with careful study and testing, creating operators can be a valuable advanced skill to have. Just be careful to not reinvent the wheel and seek guidance from the Rx community as you start dabbling in custom operators.

If you truly are interested in implementing your own operators (at a low level, not with Transformers), definitely study existing operators in RxJava and other reputable RxJava extension libraries. It is easy to hack an operator...