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 atomic variables instead of synchronization

When you have to share data between multiple threads, you have to protect access to that piece of data using a synchronization mechanism. You can use the synchronized keyword in the declaration of the method that modifies the data so that only one thread can modify data at a time. Another possibility is the utilization of a Lock class to create a critical section with instructions that modify data.

Since version 5, Java includes atomic variables. When a thread is doing an operation with an atomic variable, the implementation of the class includes a mechanism to check that the operation is done in one step. Basically, the operation gets the value of the variable, changes the value in a local variable, and then tries to change the old value with the new one. If the old value is still the same, it does the change. If not, the method begins the operation again. Java...