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 10. Testing and Debugging

While unit testing is not a silver bullet to ensure that your code works properly, it is a good practice to strive for. This is especially true if your logic is highly deterministic and modular enough to isolate.

Testing with RxJava at first glance may not seem straightforward. After all, RxJava declares behaviors rather than states. So how do we test whether behaviors are working correctly, especially when most testing frameworks expect a stateful result? Fortunately, RxJava comes with several tools to aid testing, and you can use these tools with your favorite testing frameworks. There are many testing tools available on the market that can work with RxJava, but in this chapter, we will use JUnit.

We will also cover a few tips to effectively debug RxJava programs. One of the downsides of RxJava is that when bugs occur, traditional approaches to debugging are not always effective, particularly because the stack traces are not always helpful and breakpoints...