§Integrating with Akka
Akka uses the Actor Model to raise the abstraction level and provide a better platform to build correct concurrent and scalable applications. For fault-tolerance it adopts the ‘Let it crash’ model, which has been used with great success in the telecoms industry to build applications that self-heal - systems that never stop. Actors also provide the abstraction for transparent distribution and the basis for truly scalable and fault-tolerant applications.
§The application actor system
Akka can work with several containers called
ActorSystems. An actor system manages the resources it is configured to use in order to run the actors which it contains.
A Play application defines a special actor system to be used by the application. This actor system follows the application life-cycle and restarts automatically when the application restarts.
Note: Nothing prevents you from using another actor system from within a Play application. The provided default is convenient if you only need to start a few actors without bothering to set-up your own actor system.
You can access the default application actor system using the
val myActor = Akka.system.actorOf(Props[MyActor], name = "myactor")
The default actor system configuration is read from the Play application configuration file. For example, to configure the default dispatcher of the application actor system, add these lines to the
akka.actor.debug.receive = on
Note: You can also configure any other actor system from the same file; just provide a top configuration key.
For Akka logging configuration, see configuring logging.
§Scheduling asynchronous tasks
You can schedule sending messages to actors and executing tasks (functions or
Runnable). You will get a
Cancellable back that you can call
cancel on to cancel the execution of the scheduled operation.
For example, to send a message to the
testActor every 300 microseconds:
Akka.system.scheduler.schedule(0.microsecond, 300.microsecond, testActor, "tick")
Note: This example uses implicit conversions defined in
scala.concurrent.durationto convert numbers to
Durationobjects with various time units.
Similarly, to run a block of code one seconds from now: