Book Image

Java 9 Concurrency Cookbook, Second Edition - Second Edition

By : Javier Fernández González
Book Image

Java 9 Concurrency Cookbook, Second Edition - Second Edition

By: Javier Fernández González

Overview of this book

Writing concurrent and parallel programming applications is an integral skill for any Java programmer. Java 9 comes with a host of fantastic features, including significant performance improvements and new APIs. This book will take you through all the new APIs, showing you how to build parallel and multi-threaded applications. The book covers all the elements of the Java Concurrency API, with essential recipes that will help you take advantage of the exciting new capabilities. You will learn how to use parallel and reactive streams to process massive data sets. Next, you will move on to create streams and use all their intermediate and terminal operations to process big collections of data in a parallel and functional way. Further, you’ll discover a whole range of recipes for almost everything, such as thread management, synchronization, executors, parallel and reactive streams, and many more. At the end of the book, you will learn how to obtain information about the status of some of the most useful components of the Java Concurrency API and how to test concurrent applications using different tools.
Table of Contents (12 chapters)

Using the fork/join framework instead of executors

Executors allow you to avoid the creation and management of threads. You implement tasks by implementing Runnable or Callable interfaces and sending them to the executor. It has a pool of threads and uses one of them to execute the tasks.

Java 7 provides a new kind of executor with the fork/join framework. This executor, implemented in the ForkJoinPool class, is designed for problems that can be split into smaller parts using the divide and conquer technique. When you implement a task for the fork/join framework, you have to check the size of the problem you have to resolve. If it's bigger than a predefined size, you divide the problem into two or more subcategories and create as many subtasks as the number of divisions you have made. The task sends these subtasks to the ForkJoinPool class using the fork() operation and waits for its finalization using the...