Actors, Akka and Scala: Overview

Prabhaker Mateti

An introduction to Akka, assuming Scala and Java fluency
CEG 7370 Distributed Computing

Table of Contents

• Overview of Lectures
• What is Scala?
• Actors Model
• What is Akka?

1 Overview of Lectures

1. May be 3 to 4 hours total.
2. Describe Scala minimally. Just enough to do Akka. Pretty much Ignore its (i) functional programming features, (ii) syntactic conveniences and (iii) type inference [not wholly].
3. Describe the Actors Model, comparable in depth to our treatment of SMP, AMP, Shared-Vars, Semaphores.
4. Describe Akka, an implementation of Actors. Just enough so you can re-do all the classics such as Readers/Writers, Dining Philosophers.
5. Show-and-Tell https://typesafe.com/activator.
6. WSU CEG 7370 P3 details depend on the above.

2 What is Scala?

1. Can be thought of as a modernized Java.
2. Combines OOP and Functional Programming.
3. Uses Type Inference heavily.
4. Compiles to JVM .class files.
5. Scala http://www.scala-lang.org/ is open source.
6. CEG 7370 on Scala

3 Actors Model

1. A model of distributed computation.
2. Uses AMP only.
3. No semaphores. No SMP.
4. Can we build these in Actors?
5. CEG 7370 on Actors

4 What is Akka?

1. Akka is an implementation of the Actor Model.
2. It makes practical concessions to the pure actor model.
3. Implemented as a library in Scala (and hence JVM). Akka library can be used in Java as well.
4. "Akka is a toolkit and runtime for building highly concurrent, distributed, and fault tolerant event-driven applications on the JVM" http://www.akka.io
5. Akka is open source.
6. CEG 7370 on Akka