ActorSystem

Obtains the external address of the default transport.

Consider differences in clustered and non-clustered ActorSystems. For a non-clustered ActorSystem, this will return an address without host and port. For a clustered ActorSystem, this will return the address that other nodes can use to communicate with this node.

The deadLetter address is a destination that will accept (and discard) every message sent to it.

Facilities for lookup up thread-pools from configuration.

ClassLoader wrapper which is used for reflective accesses internally. This is set to use the context class loader, if one is set, or the class loader which loaded the ActorSystem implementation. The context class loader is also set on all threads created by the ActorSystem, if one was set during creation.

Java API: Returns a CompletionStage which will be completed after the ActorSystem has been terminated and termination hooks have been executed. The ActorSystem can be stopped with ActorSystem.terminate or by stopping the guardian actor.

Be careful to not schedule any operations, such as thenRunAsync, on the dispatchers (Executor) of this actor system as they will have been shut down before this CompletionStage completes.

An ActorRef that ignores any incoming messages.

A org.slf4j.Logger that can be used to emit log messages without specifying a more detailed source. Typically it is desirable to use the dedicated Logger available from each Actor’s TypedActorContext as that ties the log entries to the actor.

Log the configuration.

The name of this actor system, used to distinguish multiple ones within the same JVM & class loader.

Create a string representation of the actor hierarchy within this system for debugging purposes.

The format of the string is subject to change, i.e. no stable “API”.

A generic scheduler that can initiate the execution of tasks after some delay. It is recommended to use the ActorContext’s scheduling capabilities for sending messages to actors instead of registering a Runnable for execution using this facility.

The core settings extracted from the supplied configuration.

Start-up time in milliseconds since the epoch.

Create an actor in the "/system" namespace. This actor will be shut down during system.terminate only after all user actors have terminated.

This is only intended to be used by libraries (and Akka itself). Applications should use ordinary spawn.

Terminates this actor system by running akka.actor.CoordinatedShutdown with reason akka.actor.CoordinatedShutdown.ActorSystemTerminateReason.

If akka.coordinated-shutdown.run-by-actor-system-terminate is configured to off it will not run CoordinatedShutdown, but the ActorSystem and its actors will still be terminated.

This will stop the guardian actor, which in turn will recursively stop all its child actors, and finally the system guardian (below which the logging actors reside).

This is an asynchronous operation and completion of the termination can be observed with ActorSystem.whenTerminated or ActorSystem.getWhenTerminated.

A ThreadFactory that can be used if the transport needs to create any Threads

Up-time of this actor system in seconds.

Scala API: Returns a Future which will be completed after the ActorSystem has been terminated. The ActorSystem can be stopped with ActorSystem.terminate or by stopping the guardian actor.

Be careful to not schedule any operations, such as onComplete, on the dispatchers (ExecutionContext) of this actor system as they will have been shut down before this future completes.

Main event bus of this actor system, used for example for logging. Accepts akka.actor.typed.eventstream.EventStream.Command.

Return a reference to this system’s akka.actor.typed.receptionist.Receptionist.

Allows access to the classic akka.actor.ActorSystem even for akka.actor.typed.ActorSystem[_]s.

Returns the payload that is associated with the provided extension throws an IllegalStateException if it is not registered. This method can potentially block, waiting for the initialization of the payload, if is in the process of registration from another Thread of execution

Returns whether the specified extension is already registered, this method can potentially block, waiting for the initialization of the payload, if is in the process of registration from another Thread of execution

Narrow the type of this ActorRef, which is always a safe operation.

The hierarchical path name of the referenced Actor. The lifecycle of the ActorRef is fully contained within the lifecycle of the akka.actor.ActorPath and more than one Actor instance can exist with the same path at different points in time, but not concurrently.

Registers the provided extension and creates its payload, if this extension isn't already registered This method has putIfAbsent-semantics, this method can potentially block, waiting for the initialization of the payload, if is in the process of registration from another Thread of execution

Send a message to the Actor referenced by this ActorRef using at-most-once messaging semantics.

Unsafe utility method for widening the type accepted by this ActorRef; provided to avoid having to use asInstanceOf on the full reference type, which would unfortunately also work on non-ActorRefs. Use it with caution,it may cause a ClassCastException when you send a message to the widened ActorRef.

The default thread pool of this ActorSystem, configured with settings in akka.actor.default-dispatcher.