What happened to akka.util.duration?

In a lot of old Akka examples you will see the following statements:

import akka.util.Timeout
import akka.util.duration._
implicit val askTimeout = Timeout(1 second)

This will give error ‘object duration is not a member of package akka.util’. It turns out duration is now included in Scala standard library. To fix the error use the following import statement:

import scala.concurrent.duration._

Check out the migration guide for other pieces of Akka functionality that have moved to Scala.

Adding custom application settings to Akka’s configuration file

Just added custom application settings to Akka’s configuration file. Retrieving these settings is kind of a mission. This is the statement to retrieve a setting:


Hmmm, putting these statements everywhere in my code does not feel right, does it? Continue reading

ClassNotFoundException when adding slf4j to Akka

When adding to a Akka project I got the following error java.lang.ClassNotFoundException: akka.event.slf4j.Slf4jLogger. I double checked my configuration and the Akka documentation. The documentation says the following:

Akka provides a logger for SL4FJ. This module is available in the ‘akka-slf4j.jar’. It has one single dependency; the slf4j-api jar. In runtime you also need a SLF4J backend, we recommend Logback.

No success. Continue reading

“value ? is not a member of akka.actor.ActorRef”

I was trying to use a Future in Akka today and got the following error message:

value ? is not a member of akka.actor.ActorRef

It turns out you have to import the akka.pattern.ask to use ‘?’. There is a implicit conversion from ActorRef to AskableActorRef.

So add the following import and you should be set to go (take note that ask does not start with a capital:

import akka.pattern.ask

Adding the latest release of Akka to an SBT project

A quick note how to create a SBT project with the latest release of Akka.

Create a build.sbt file:

name := "ScalaAkkaTest"

organization := "<Your organisation name>"

version := "0.1.0-SNAPSHOT"

scalaVersion := "2.11.2"

resolvers += "Typesafe Repository" at "http://repo.typesafe.com/typesafe/releases/"

libraryDependencies += "com.typesafe.akka" %% "akka-actor" % "2.3.6"

Continue reading