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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This chapter presented some powerful abstractions for asynchronous programming. We have seen how to encode latency with the Future type, how to avoid blocking with callbacks on futures, and how to compose values from multiple futures. We have learned that futures and promises are closely tied together and that promises allow interfacing with legacy callback-based systems. In cases where blocking was unavoidable, we learned how to use the Await object and the blocking statement. Finally, we learned that the Scala Async library is a powerful alternative for expressing future computations more concisely.

Futures and promises only allow dealing with a single value at a time. What if an asynchronous computation produces more than a single value before completing? Similarly, how do we efficiently execute thousands of asynchronous operations on different elements of large datasets? Should we use futures in such cases? In the next chapter, we will explore Scala's support for data-parallelism...