Book Image

Learning Concurrent Programming in Scala - Second Edition

By : Aleksandar Prokopec
Book Image

Learning Concurrent Programming in Scala - Second Edition

By: Aleksandar Prokopec

Overview of this book

Scala is a modern, multiparadigm programming language designed to express common programming patterns in a concise, elegant, and type-safe way. Scala smoothly integrates the features of object-oriented and functional languages. In this second edition, you will find updated coverage of the Scala 2.12 platform. The Scala 2.12 series targets Java 8 and requires it for execution. The book starts by introducing you to the foundations of concurrent programming on the JVM, outlining the basics of the Java Memory Model, and then shows some of the classic building blocks of concurrency, such as the atomic variables, thread pools, and concurrent data structures, along with the caveats of traditional concurrency. The book then walks you through different high-level concurrency abstractions, each tailored toward a specific class of programming tasks, while touching on the latest advancements of async programming capabilities of Scala. It also covers some useful patterns and idioms to use with the techniques described. Finally, the book presents an overview of when to use which concurrency library and demonstrates how they all work together, and then presents new exciting approaches to building concurrent and distributed systems. Who this book is written for If you are a Scala programmer with no prior knowledge of concurrent programming, or seeking to broaden your existing knowledge about concurrency, this book is for you. Basic knowledge of the Scala programming language will be helpful.
Table of Contents (19 chapters)
Learning Concurrent Programming in Scala - Second Edition
About the Author
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Remote actors

So far in this book, we have mostly concentrated on writing programs on a single computer. Concurrent programs are executed within a single process on one computer, and they communicate using shared memory. Seemingly, actors described in this chapter communicate by passing messages. However, the message passing used throughout this chapter is implemented by reading and writing to shared memory under the hood.

In this section, we study how the actor model ensures location transparency by taking existing actors and deploying them in a distributed program. We take two existing actor implementations, namely, Pingy and Pongy, and deploy them inside different processes. We will then instruct the Pingy actor to send a message to the Pongy actor, as before, and wait until the Pingy actor returns the Pongy actor's message. The message exchange will occur transparently, although the Pingy and Pongy actor's were previously implemented without knowing that they might exist inside separate...