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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In the following exercises, you will need to implement different Observable objects. The exercises show different use cases for Observable objects, and contrast the different ways of creating Observable objects. Also, some of the exercises introduce new reactive programming abstractions, such as reactive maps and reactive priority queues.

  1. Implement a custom Observable[Thread] object that emits an event when it detects that a thread was started. The implementation is allowed to miss some of the events.

  2. Implement an Observable object that emits an event every 5 seconds and every 12 seconds, but not if the elapsed time is a multiple of 30 seconds. Use functional combinators on Observable objects.

  3. Use the randomQuote method from this section in order to create an Observable object with the moving average of the quote lengths. Each time a new quote arrives, a new average value should be emitted.

  4. Implement the reactive signal abstraction, represented with the Signal[T] type. The type Signal...