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 covered combining Observables in various useful ways. Merging is helpful in combining and simultaneously firing multiple Observables and combining their emissions into a single stream. The flatMap() operator is especially critical to know, as dynamically merging Observables derived from emissions opens a lot of useful functionality in RxJava. Concatenation is similar to merging, but it fires off the source Observables sequentially rather than all at once. Combining with ambiguous allows us to select the first Observable to emit and fire its emissions. Zipping allows you to combine emissions from multiple Observables, whereas combine latest combines the latest emissions from each source every time one of them fires. Finally, grouping allows you to split up an Observable into several GroupedObservables,  each with emissions that have a common key. 

Take time to explore combining Observables and experiment to see how they work. They are critical to unlock functionalities...