Book Image

Mastering Concurrency Programming with Java 9, Second Edition - Second Edition

By : Javier Fernández González
Book Image

Mastering Concurrency Programming with Java 9, Second Edition - 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
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Dedication
Preface

An introduction to the fork/join framework


The executor framework, introduced in Java 5, provides a mechanism to execute concurrent tasks without creating, starting, and finishing threads. This framework uses a pool of threads that executes the tasks you send to the executor, reusing them for multiple tasks. This mechanism provides the following advantages to programmers:

  • It's easier to program concurrent applications because you don't have to worry about creating threads.
  • It's easier to control the resources used by the executor and your application. You can create an executor that only uses a predefined number of threads. If you send more threads, the executor stores them in a queue until a thread is available.
  • Executors reduce the overhead introduced by thread creation by reusing the threads. Internally, it manages a pool of threads that reuses threads to execute multiple tasks.

The divide and conquer algorithm is a very popular design technique. To solve a problem using this technique, you...