Book Image

Java 9 Concurrency Cookbook, Second Edition - Second Edition

By : Javier Fernández González
Book Image

Java 9 Concurrency Cookbook, Second Edition - Second Edition

By: Javier Fernández González

Overview of this book

Writing concurrent and parallel programming applications is an integral skill for any Java programmer. Java 9 comes with a host of fantastic features, including significant performance improvements and new APIs. This book will take you through all the new APIs, showing you how to build parallel and multi-threaded applications. The book covers all the elements of the Java Concurrency API, with essential recipes that will help you take advantage of the exciting new capabilities. You will learn how to use parallel and reactive streams to process massive data sets. Next, you will move on to create streams and use all their intermediate and terminal operations to process big collections of data in a parallel and functional way. Further, you’ll discover a whole range of recipes for almost everything, such as thread management, synchronization, executors, parallel and reactive streams, and many more. At the end of the book, you will learn how to obtain information about the status of some of the most useful components of the Java Concurrency API and how to test concurrent applications using different tools.
Table of Contents (12 chapters)

Implementing your own asynchronous stream

Reactive streams (http://www.reactive-streams.org/) defines a mechanism to provide asynchronous stream processing with non-blocking back pressure.

Reactive streams are based on three elements:

  • It is a publisher of information
  • It has one or more subscribers of this information
  • It provides subscription between the publisher and a consumer

Java 9 has included three interfaces--Flow.Publisher, Flow.Subscriber, and Flow.Subscription--and a utility class, SubmissionPublisher, to allow us to implement reactive stream applications.

In this recipe, you will learn how to implement your own reactive application using only three interfaces. Take into account that we will implement the expected behavior between the three elements. The publisher will only send elements to those subscribers who have requested them, and it will do this in a concurrent way. But you can modify this behavior...