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

Chapter 8. Flowables and Backpressure

In the previous chapter, we learned about different operators that intercept rapidly firing emissions and either consolidate or omit them to decrease the emissions passed downstream. But for most cases where a source is producing emissions faster than the downstream can process them, it is better to proactively make the source slow down in the first place and emit at a pace that agrees with the downstream operations. This is known as backpressure or flow control, and it can be enabled by using a Flowable instead of an Observable. This will be the core type that we work with in this chapter, and we will learn about the right times to leverage it in our applications. We will cover the following topics in this chapter:

  • Understanding backpressure
  • Flowable and Subscriber
  • Using Flowable.create()
  • Interoperating Observables and Flowables
  • Backpressure operators
  • Using Flowable.generate()