Book Image

Akka Cookbook

By : Vivek Mishra, Héctor Veiga Ortiz
Book Image

Akka Cookbook

By: Vivek Mishra, Héctor Veiga Ortiz

Overview of this book

Akka is an open source toolkit that simplifies the construction of distributed and concurrent applications on the JVM. This book will teach you how to develop reactive applications in Scala using the Akka framework. This book will show you how to build concurrent, scalable, and reactive applications in Akka. You will see how to create high performance applications, extend applications, build microservices with Lagom, and more. We will explore Akka's actor model and show you how to incorporate concurrency into your applications. The book puts a special emphasis on performance improvement and how to make an application available for users. We also make a special mention of message routing and construction. By the end of this book, you will be able to create a high-performing Scala application using the Akka framework.
Table of Contents (18 chapters)
Title Page
About the Authors
About the Reviewer
Customer Feedback

Sending messages to actors and collecting responses

In this recipe, you will learn how a parent sends messages to its child, and collects responses from them.

To step through this recipe, we need to import the Hello-Akka project in the IDE.

How to do it...

  1. Create a file, SendMesagesToChilds.scala, in package com.packt.chapter2.
  2. Add the following imports to the top of the file:
        import{ Props, ActorSystem, Actor, ActorRef } 
  1. Create messages to be sent to the actors as follows:
        case class DoubleValue(x: Int) 
        case object CreateChild 
        case object Send 
        case class Response(x: Int) 
  1. Define a child actor. It doubles the value sent to it.
        class DoubleActor extends Actor { 
          def receive = { 
            case DoubleValue(number) =>  
            println(s"${} Got the number $number") 
            sender ! Response(number * 2) 
  1. Define a parent actor. It creates child actors in its context, sends messages...