Book Image

Mastering Concurrency Programming with Java 9 - Second Edition

By : Javier Fernández González
Book Image

Mastering Concurrency Programming with Java 9 - Second Edition

By: Javier Fernández González

Overview of this book

Concurrency programming allows several large tasks to be divided into smaller sub-tasks, which are further processed as individual tasks that run in parallel. Java 9 includes a comprehensive API with lots of ready-to-use components for easily implementing powerful concurrency applications, but with high flexibility so you can adapt these components to your needs. The book starts with a full description of the design principles of concurrent applications and explains how to parallelize a sequential algorithm. You will then be introduced to Threads and Runnables, which are an integral part of Java 9's concurrency API. You will see how to use all the components of the Java concurrency API, from the basics to the most advanced techniques, and will implement them in powerful real-world concurrency applications. The book ends with a detailed description of the tools and techniques you can use to test a concurrent Java application, along with a brief insight into other concurrency mechanisms in JVM.
Table of Contents (21 chapters)
Title Page
About the Author
About the Reviewer
Customer Feedback

The second example - a news system

In the previous example, we used the SubmissionPublisher class, so we didn't implement the Flow.Publisher and the Flow.Subscription interfaces. If the functionality provided by the SubmissionPublisher doesn't fit our needs, we will have to implement our own publisher and subscription.

In this section, you will learn how to implement both interfaces to learn the specification of the reactive streams. We are going to implement a news system where each piece of news will be associated with a category. A subscriber will be subscribed to one or more categories and the publisher will only send a piece of news to each subscriber if it's subscribed to its category.

The News class

The first class we're going to implement is the News class. This class represents each piece of news we're going to send from the publisher to the consumer. We're going to store three attributes:

  • Thecategory attribute: An int value that stores the category of the news. It can take the values...