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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The following exercises test your understanding of the actor programming model, and distributed programming in general. The first few exercises are straightforward, and deal with the basics of the actor API in Akka. Subsequent exercises are more involved, and go deeper into the territory of fault-tolerant distributed programming. Try to solve these exercises by first assuming that no machines fail, and then consider what happens if some of the machines fail during the execution of the program:

  1. Implement the timer actor with the TimerActor class. After receiving a Register message containing the t timeout in milliseconds, the timer actor sends a Timeout message back after t milliseconds. The timer must accept multiple Register messages.

  2. Recall the bank account example from Chapter 2, Concurrency on the JVM and the Java Memory Model. Implement different bank accounts as separate actors, represented by the AccountActor class. When an AccountActor class receives a Send message, it must...