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)

Completing and linking tasks asynchronously

Java 8 Concurrency API includes a new synchronization mechanism with the CompletableFuture class. This class implements the Future object and the CompletionStage interface that gives it the following two characteristics:

  • As the Future object, a CompletableFuture object will return a result sometime in future
  • As the CompletionStage object, you can execute more asynchronous tasks after the completion of one or more CompletableFuture objects

You can work with a CompletableFuture class in different ways:

  • You can create a CompletableFuture object explicitly and use it as a synchronization point between tasks. One task will establish the value returned by CompletableFuture, using the complete() method, and the other tasks will wait for this value, using the get() or join() methods.
  • You can use a static method of the CompletableFuture class to execute Runnable or Supplier...