Packages

abstract class ActorSystem extends ActorRefFactory with ClassicActorSystemProvider

An actor system is a hierarchical group of actors which share common configuration, e.g. dispatchers, deployments, remote capabilities and addresses. It is also the entry point for creating or looking up actors.

There are several possibilities for creating actors (see akka.actor.Props for details on props):

// Java or Scala
system.actorOf(props, "name")
system.actorOf(props)

// Scala
system.actorOf(Props[MyActor], "name")
system.actorOf(Props(classOf[MyActor], arg1, arg2), "name")

// Java
system.actorOf(Props.create(MyActor.class), "name");
system.actorOf(Props.create(MyActor.class, arg1, arg2), "name");

Where no name is given explicitly, one will be automatically generated.

Important Notice:

This class is not meant to be extended by user code. If you want to actually roll your own Akka, it will probably be better to look into extending akka.actor.ExtendedActorSystem instead, but beware that you are completely on your own in that case!

Source
ActorSystem.scala
Linear Supertypes
ClassicActorSystemProvider, ActorRefFactory, AnyRef, Any
Known Subclasses
ExtendedActorSystem
Type Hierarchy
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. ActorSystem
  2. ClassicActorSystemProvider
  3. ActorRefFactory
  4. AnyRef
  5. Any
Implicitly
  1. by any2stringadd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
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Visibility
  1. Public
  2. Protected

Instance Constructors

  1. new ActorSystem()

Abstract Value Members

  1. abstract def /(name: Iterable[String]): ActorPath

    Construct a path below the application guardian to be used with ActorSystem#actorSelection.

  2. abstract def /(name: String): ActorPath

    Construct a path below the application guardian to be used with ActorSystem#actorSelection.

  3. abstract def actorOf(props: Props, name: String): ActorRef

    Create new actor as child of this context with the given name, which must not be null, empty or start with “$”.

    Create new actor as child of this context with the given name, which must not be null, empty or start with “$”. If the given name is already in use, an InvalidActorNameException is thrown.

    See akka.actor.Props for details on how to obtain a Props object.

    Definition Classes
    ActorRefFactory
    Exceptions thrown

    UnsupportedOperationException if invoked on an ActorSystem that uses a custom user guardian

    akka.ConfigurationException if deployment, dispatcher or mailbox configuration is wrong

    akka.actor.InvalidActorNameException if the given name is invalid or already in use

  4. abstract def actorOf(props: Props): ActorRef

    Create new actor as child of this context and give it an automatically generated name (currently similar to base64-encoded integer count, reversed and with “$” prepended, may change in the future).

    Create new actor as child of this context and give it an automatically generated name (currently similar to base64-encoded integer count, reversed and with “$” prepended, may change in the future).

    See akka.actor.Props for details on how to obtain a Props object.

    Definition Classes
    ActorRefFactory
    Exceptions thrown

    UnsupportedOperationException if invoked on an ActorSystem that uses a custom user guardian

    akka.ConfigurationException if deployment, dispatcher or mailbox configuration is wrong

  5. abstract def classicSystem: ActorSystem

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

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

    Definition Classes
    ClassicActorSystemProvider
  6. abstract def deadLetters: ActorRef

    Actor reference where messages are re-routed to which were addressed to stopped or non-existing actors.

    Actor reference where messages are re-routed to which were addressed to stopped or non-existing actors. Delivery to this actor is done on a best effort basis and hence not strictly guaranteed.

  7. implicit abstract def dispatcher: ExecutionContextExecutor

    Default dispatcher as configured.

    Default dispatcher as configured. This dispatcher is used for all actors in the actor system which do not have a different dispatcher configured explicitly. Importing this member will place the default MessageDispatcher in scope.

    Definition Classes
    ActorSystem → ActorRefFactory
  8. abstract def dispatchers: Dispatchers

    Helper object for looking up configured dispatchers.

  9. abstract def eventStream: EventStream

    Main event bus of this actor system, used for example for logging.

  10. abstract def extension[T <: Extension](ext: ExtensionId[T]): T

    Returns the payload that is associated with the provided extension throws an IllegalStateException if it is not registered.

    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

  11. abstract def getWhenTerminated: CompletionStage[Terminated]

    Returns a CompletionStage which will be completed after the ActorSystem has been terminated and termination hooks have been executed.

    Returns a CompletionStage which will be completed after the ActorSystem has been terminated and termination hooks have been executed. If you registered any callback with ActorSystem#registerOnTermination, the returned CompletionStage from this method will not complete until all the registered callbacks are finished. 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.

  12. abstract def guardian: InternalActorRef

    Parent of all children created by this interface.

    Parent of all children created by this interface.

    INTERNAL API

    Attributes
    protected
    Definition Classes
    ActorRefFactory
  13. abstract def hasExtension(ext: ExtensionId[_ <: Extension]): Boolean

    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

  14. abstract def log: LoggingAdapter

    Convenient logging adapter for logging to the ActorSystem#eventStream.

  15. abstract def logConfiguration(): Unit

    Log the configuration.

  16. abstract def lookupRoot: InternalActorRef

    INTERNAL API

    INTERNAL API

    Attributes
    protected
    Definition Classes
    ActorRefFactory
  17. abstract def mailboxes: Mailboxes

    Helper object for looking up configured mailbox types.

  18. abstract def name: String

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

  19. abstract def provider: ActorRefProvider

    INTERNAL API

    INTERNAL API

    Attributes
    protected
    Definition Classes
    ActorRefFactory
  20. abstract def registerExtension[T <: Extension](ext: ExtensionId[T]): T

    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

  21. abstract def registerOnTermination(code: Runnable): Unit

    Java API: Register a block of code (callback) to run after ActorSystem.terminate has been issued and all actors in this actor system have been stopped.

    Java API: Register a block of code (callback) to run after ActorSystem.terminate has been issued and all actors in this actor system have been stopped. Multiple code blocks may be registered by calling this method multiple times. The callbacks will be run sequentially in reverse order of registration, i.e. last registration is run first. Note that ActorSystem will not terminate until all the registered callbacks are finished.

    Throws a RejectedExecutionException if the System has already been terminated or if termination has been initiated.

  22. abstract def registerOnTermination[T](code: => T): Unit

    Register a block of code (callback) to run after ActorSystem.terminate has been issued and all actors in this actor system have been stopped.

    Register a block of code (callback) to run after ActorSystem.terminate has been issued and all actors in this actor system have been stopped. Multiple code blocks may be registered by calling this method multiple times. The callbacks will be run sequentially in reverse order of registration, i.e. last registration is run first. Note that ActorSystem will not terminate until all the registered callbacks are finished.

    Throws a RejectedExecutionException if the System has already been terminated or if termination has been initiated.

    Scala API

  23. abstract def scheduler: Scheduler

    Light-weight scheduler for running asynchronous tasks after some deadline in the future.

    Light-weight scheduler for running asynchronous tasks after some deadline in the future. Not terribly precise but cheap.

  24. abstract def settings: Settings

    The core settings extracted from the supplied configuration.

  25. abstract def stop(actor: ActorRef): Unit

    Stop the actor pointed to by the given akka.actor.ActorRef; this is an asynchronous operation, i.e.

    Stop the actor pointed to by the given akka.actor.ActorRef; this is an asynchronous operation, i.e. involves a message send. If this method is applied to the self reference from inside an Actor then that Actor is guaranteed to not process any further messages after this call; please note that the processing of the current message will continue, this method does not immediately terminate this actor.

    Definition Classes
    ActorRefFactory
  26. abstract def systemImpl: ActorSystemImpl

    INTERNAL API

    INTERNAL API

    Attributes
    protected
    Definition Classes
    ActorRefFactory
  27. abstract def terminate(): Future[Terminated]

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

    Terminates this actor system by running CoordinatedShutdown with reason 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) and then execute all registered termination handlers (see ActorSystem#registerOnTermination). Be careful to not schedule any operations on completion of the returned future using the dispatcher of this actor system as it will have been shut down before the future completes.

  28. abstract def whenTerminated: Future[Terminated]

    Returns a Future which will be completed after the ActorSystem has been terminated and termination hooks have been executed.

    Returns a Future which will be completed after the ActorSystem has been terminated and termination hooks have been executed. If you registered any callback with ActorSystem#registerOnTermination, the returned Future from this method will not complete until all the registered callbacks are finished. 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.

Concrete Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##: Int
    Definition Classes
    AnyRef → Any
  3. def +(other: String): String
    Implicit
    This member is added by an implicit conversion from ActorSystem toany2stringadd[ActorSystem] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. def ->[B](y: B): (ActorSystem, B)
    Implicit
    This member is added by an implicit conversion from ActorSystem toArrowAssoc[ActorSystem] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  5. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  6. def actorSelection(path: ActorPath): ActorSelection

    Construct an akka.actor.ActorSelection from the given path, which is parsed for wildcards (these are replaced by regular expressions internally).

    Construct an akka.actor.ActorSelection from the given path, which is parsed for wildcards (these are replaced by regular expressions internally). No attempt is made to verify the existence of any part of the supplied path, it is recommended to send a message and gather the replies in order to resolve the matching set of actors.

    Definition Classes
    ActorRefFactory
  7. def actorSelection(path: String): ActorSelection

    Construct an akka.actor.ActorSelection from the given path, which is parsed for wildcards (these are replaced by regular expressions internally).

    Construct an akka.actor.ActorSelection from the given path, which is parsed for wildcards (these are replaced by regular expressions internally). No attempt is made to verify the existence of any part of the supplied path, it is recommended to send a message and gather the replies in order to resolve the matching set of actors.

    Definition Classes
    ActorRefFactory
  8. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  9. def child(child: String): ActorPath

    Java API: Create a new child actor path.

  10. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.CloneNotSupportedException]) @HotSpotIntrinsicCandidate() @native()
  11. def descendant(names: Iterable[String]): ActorPath

    Java API: Recursively create a descendant’s path by appending all child names.

  12. def ensuring(cond: (ActorSystem) => Boolean, msg: => Any): ActorSystem
    Implicit
    This member is added by an implicit conversion from ActorSystem toEnsuring[ActorSystem] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  13. def ensuring(cond: (ActorSystem) => Boolean): ActorSystem
    Implicit
    This member is added by an implicit conversion from ActorSystem toEnsuring[ActorSystem] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  14. def ensuring(cond: Boolean, msg: => Any): ActorSystem
    Implicit
    This member is added by an implicit conversion from ActorSystem toEnsuring[ActorSystem] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  15. def ensuring(cond: Boolean): ActorSystem
    Implicit
    This member is added by an implicit conversion from ActorSystem toEnsuring[ActorSystem] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  16. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  17. def equals(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef → Any
  18. final def getClass(): Class[_ <: AnyRef]
    Definition Classes
    AnyRef → Any
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  19. def getDispatcher: ExecutionContextExecutor

    Java API: Default dispatcher as configured.

    Java API: Default dispatcher as configured. This dispatcher is used for all actors in the actor system which do not have a different dispatcher configured explicitly. Importing this member will place the default MessageDispatcher in scope.

  20. def getEventStream: EventStream

    Java API: Main event bus of this actor system, used for example for logging.

  21. def getScheduler: Scheduler

    Java API: Light-weight scheduler for running asynchronous tasks after some deadline in the future.

    Java API: Light-weight scheduler for running asynchronous tasks after some deadline in the future. Not terribly precise but cheap.

  22. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  23. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  24. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  25. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  26. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @HotSpotIntrinsicCandidate() @native()
  27. val startTime: Long

    Start-up time in milliseconds since the epoch.

  28. final def synchronized[T0](arg0: => T0): T0
    Definition Classes
    AnyRef
  29. def toString(): String
    Definition Classes
    AnyRef → Any
  30. def uptime: Long

    Up-time of this actor system in seconds.

  31. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])
  32. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException]) @native()
  33. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.InterruptedException])

Deprecated Value Members

  1. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws(classOf[java.lang.Throwable]) @Deprecated
    Deprecated

    (Since version 9)

  2. def formatted(fmtstr: String): String
    Implicit
    This member is added by an implicit conversion from ActorSystem toStringFormat[ActorSystem] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @deprecated @inline()
    Deprecated

    (Since version 2.12.16) Use formatString.format(value) instead of value.formatted(formatString), or use the f"" string interpolator. In Java 15 and later, formatted resolves to the new method in String which has reversed parameters.

  3. def →[B](y: B): (ActorSystem, B)
    Implicit
    This member is added by an implicit conversion from ActorSystem toArrowAssoc[ActorSystem] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @deprecated
    Deprecated

    (Since version 2.13.0) Use -> instead. If you still wish to display it as one character, consider using a font with programming ligatures such as Fira Code.

Inherited from ClassicActorSystemProvider

Inherited from ActorRefFactory

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd fromActorSystem to any2stringadd[ActorSystem]

Inherited by implicit conversion StringFormat fromActorSystem to StringFormat[ActorSystem]

Inherited by implicit conversion Ensuring fromActorSystem to Ensuring[ActorSystem]

Inherited by implicit conversion ArrowAssoc fromActorSystem to ArrowAssoc[ActorSystem]

Ungrouped