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

An introduction to executors

As we explain in Chapter 2, Working with Basic Elements - Threads and Runnables, the basic mechanism to implement a concurrent application in Java is:

  • A class that implements theRunnable interface: This is the code you want to implement in a concurrent way
  • An instance of theThread class: This is the thread that is going to execute the code in a concurrent way

With this approach, you're responsible for creating and manning the thread objects and implementing the mechanisms of synchronization between the threads. However, it can create some problems, especially with those applications with a lot of concurrent tasks. If you create too many threads, you can degrade the performance of your application or even hang the entire system.

Java version 5 included the Executor framework to solve these problems and provide an efficient solution that is easier to use for programmers than the traditional concurrency mechanisms.

In this chapter, we will introduce the basic characteristics...