Typesafe Activator

Akka FSM in Scala

Akka FSM in Scala

Akka Team
Source
June 30, 2014
akka scala sample

Illustrating how to implement a finite state machine in actors.

How to get "Akka FSM in Scala" on your computer

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Option 2: Download the akka-sample-fsm-scala project as a zip archive

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  1. Download the Template Bundle for "Akka FSM in Scala"
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Option 3: Create a akka-sample-fsm-scala project from the command line

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Option 4: View the template source

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Option 5: Preview the tutorial below

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Preview the tutorial

Finite State Machine in Actors

This sample is an adaptation of Dining Hakkers. It illustrates how state and behavior can be managed within an Actor with two different approaches; using become and using the FSM trait.

Dining Hakkers with Become

Open DiningHakkersOnBecome.scala.

It illustrates how current behavior can be replaced with context.become. Note that no var members are used, instead the state is encoded in the current behavior and its parameters.

Go to the Run tab, and start the application main class sample.become.DiningHakkersOnBecome. In the log output you can see the actions of the Hakker actors.

Read more about become in the documentation.

Dining Hakkers with FSM

Open DiningHakkersOnFsm.scala.

It illustrates how the states and transitions can be defined with the akka.actor.FSM trait.

Go to the Run tab, and start the application main class sample.fsm.DiningHakkersOnFsm. In the log output you can see the actions of the Hakker actors.

Read more about akka.actor.FSM in the documentation.

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