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)

Collecting the elements of a stream

Java streams allow you to process a sequence of elements in a sequential or parallel way. You can create a stream from different data sources, as a Collection, a File or an Array and apply to its elements a sequence of operations normally defined with lambda expressions. Those operations can be divided into two different classes:

  • Intermediate operations: These operations return other Stream as a result and allow you to filter, transform, or sort the elements of the stream
  • Terminal operations: These operations return a result after processing the elements of the stream

A stream has a source, zero or more intermediate operations, and a terminal operation. The two most important terminal operations are:

  • The reduce operation, which allows you to obtain a unique result after processing the elements of the stream. This result usually is a summary of the processed data. The Reducing...