Akka/Scala example source code file (OsgiActorSystemFactory.scala)

This example Akka source code file (OsgiActorSystemFactory.scala) is included in my "Source Code Warehouse" project. The intent of this project is to help you more easily find Akka and Scala source code examples by using tags.

All credit for the original source code belongs to akka.io; I'm just trying to make examples easier to find. (For my Scala work, see my Scala examples and tutorials.)

Akka tags/keywords

actor, actorsystem, akka, bundlecontext, bundledelegatingclassloader, config, option, osgi, osgiactorsystemfactory, some, string

The OsgiActorSystemFactory.scala Akka example source code

/**
 * Copyright (C) 2009-2014 Typesafe Inc. <http://www.typesafe.com>
 */
package akka.osgi

import akka.actor.ActorSystem
import com.typesafe.config.{ ConfigFactory, Config }
import org.osgi.framework.BundleContext
import java.io.File

/**
 * Factory class to create ActorSystem implementations in an OSGi environment.  This mainly involves dealing with
 * bundle classloaders appropriately to ensure that configuration files and classes get loaded properly
 */
class OsgiActorSystemFactory(val context: BundleContext, val fallbackClassLoader: Option[ClassLoader], config: Config = ConfigFactory.empty) {

  /*
   * Classloader that delegates to the bundle for which the factory is creating an ActorSystem
   */
  private val classloader = BundleDelegatingClassLoader(context, fallbackClassLoader)

  /**
   * Creates the [[akka.actor.ActorSystem]], using the name specified
   */
  def createActorSystem(name: String): ActorSystem = createActorSystem(Option(name))

  /**
   * Creates the [[akka.actor.ActorSystem]], using the name specified.
   *
   * A default name (`bundle-<bundle id>-ActorSystem`) is assigned when you pass along [[scala.None]] instead.
   */
  def createActorSystem(name: Option[String]): ActorSystem =
    ActorSystem(actorSystemName(name), actorSystemConfig(context), classloader)

  /**
   * Strategy method to create the Config for the ActorSystem
   * ensuring that the default/reference configuration is loaded from the akka-actor bundle.
   * Configuration files found in akka-actor bundle
   */
  def actorSystemConfig(context: BundleContext): Config = {
    config.withFallback(ConfigFactory.load(classloader).withFallback(ConfigFactory.defaultReference(OsgiActorSystemFactory.akkaActorClassLoader)))
  }

  /**
   * Determine the name for the [[akka.actor.ActorSystem]]
   * Returns a default value of `bundle-<bundle id>-ActorSystem` is no name is being specified
   */
  def actorSystemName(name: Option[String]): String =
    name.getOrElse("bundle-%s-ActorSystem".format(context.getBundle.getBundleId))

}

object OsgiActorSystemFactory {
  /**
   * Class loader of akka-actor bundle.
   */
  def akkaActorClassLoader = classOf[ActorSystemActivator].getClassLoader

  /*
   * Create an [[OsgiActorSystemFactory]] instance to set up Akka in an OSGi environment
   */
  def apply(context: BundleContext, config: Config): OsgiActorSystemFactory = new OsgiActorSystemFactory(context, Some(akkaActorClassLoader), config)
}