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


In this chapter, we explained one of the most powerful synchronization mechanisms provided by the Java concurrency API: the phaser. Its main objective is to provide synchronization between tasks that execute algorithms divided into phases. None of the tasks can begin the execution of a phase before the rest of the tasks have finished the previous one.

The phaser has to know how many tasks have to be synchronized. You have to register your tasks in the phaser using the constructor, the bulkRegister() method, or the register() method.

Tasks can synchronize with the phaser in different ways. The most common task is indicating to the phaser that it has finished the execution of one phase and wants to continue with the next one with the arriveAndAwaitAdvance(). This method will sleep the thread until the rest of the tasks have finished the actual phase. But there are other methods you can use to synchronize your tasks. The arrive() method is used to notify the phaser that you have finished...