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

Additional information about executors

In this chapter, we have extended ThreadPoolExecutor and the ScheduledThreadPoolExecutor class, and overridden some of their methods. But you can override more methods if you want a more specific behavior. These are some methods you can override:

  • shutdown(): You must explicitly call this method to end the execution of the executor. You can override it to add some code to free additional resources used by your own executor.
  • shutdownNow(): The difference between shutdown() and shutdownNow() is that the shutdown() method waits for the finalization of all the tasks that are waiting in the executor.
  • submit(), invokeall(), or invokeany(): You call these methods to send concurrent tasks to the executor. You can override them if you need to do some actions before or after a task is inserted in the task queue of the executor. Note that adding a custom action before or after the task is enqueued is different from adding a custom action before or after it's executed...