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 use ScalaSTM to implement various transactional programming abstractions. In most cases, their implementation will closely resemble a sequential implementation, while using transactions. In some cases, you might need to consult external literature or ScalaSTM documentation to correctly solve the exercise.

  1. Implement the transactional pair abstraction, represented with the TPair class:

            class TPair[P, Q](pinit: P, qinit: Q) { 
              def first(implicit txn: InTxn): P = ??? 
              def first_=(x: P)(implicit txn: InTxn): P = ??? 
              def second(implicit txn: InTxn): Q = ??? 
              def second_=(x: Q)(implicit txn: InTxn): Q = ??? 
              def swap()(implicit e: P =:= Q, txn: InTxn): Unit = ??? 

    In addition to getters and setters for the two fields, the transactional pair defines the swap method that swaps the fields, and can only be called if types P and Q are the same.

  2. Use ScalaSTM...