Book Image

Learning RxJava

By : Nield
Book Image

Learning RxJava

By: 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 (14 chapters)

Buffering

The buffer() operator will gather emissions within a certain scope and emit each batch as a list or another collection type. The scope can be defined by a fixed buffer sizing or a timing window that cuts off at intervals or even slices by the emissions of another Observable.

Fixed-size buffering

The simplest overload for buffer() accepts a count argument that batches emissions in that fixed size. If we wanted to batch up emissions into lists of eight elements, we can do that as follows:

import io.reactivex.Observable;

public class Launcher {
public static void main(String[] args) {
Observable.range(1,50)
.buffer(8)
.subscribe(System.out::println);
}
}

The output is as...