trait EntityRef[-M] extends RecipientRef[M]

A reference to an sharded Entity, which allows ActorRef-like usage.

An EntityRef is NOT an ActorRef–by design–in order to be explicit about the fact that the life-cycle of a sharded Entity is very different than a plain Actors. Most notably, this is shown by features of Entities such as re-balancing (an active Entity to a different node) or passivation. Both of which are aimed to be completely transparent to users of such Entity. In other words, if this were to be a plain ActorRef, it would be possible to apply DeathWatch to it, which in turn would then trigger when the sharded Actor stopped, breaking the illusion that Entity refs are "always there". Please note that while not encouraged, it is possible to expose an Actor's self ActorRef and watch it in case such notification is desired. Not for user extension.

Self Type
EntityRef[M] with InternalRecipientRef[M]
Annotations
@DoNotInherit()
Source
ClusterSharding.scala
Linear Supertypes
RecipientRef[M], AnyRef, Any
Type Hierarchy
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. EntityRef
  2. RecipientRef
  3. AnyRef
  4. Any
Implicitly
  1. by RecipientRefOps
  2. by any2stringadd
  3. by StringFormat
  4. by Ensuring
  5. by ArrowAssoc
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. Protected

Abstract Value Members

  1. abstract def ask[Res](f: (ActorRef[Res]) => M)(implicit timeout: Timeout): Future[Res]

    Allows to "ask" the EntityRef for a reply.

    Allows to "ask" the for a reply. See akka.actor.typed.scaladsl.AskPattern for a complete write-up of this pattern

    Note that if you are inside of an actor you should prefer akka.actor.typed.scaladsl.ActorContext.ask as that provides better safety.

    Example usage:

    case class Request(msg: String, replyTo: ActorRef[Reply])
case class Reply(msg: String)

implicit val timeout = Timeout(3.seconds)
val target: EntityRef[Request] = ...
val f: Future[Reply] = target.ask(Request("hello", _))

    Please note that an implicit akka.util.Timeout must be available to use this pattern.

    Res

    The response protocol, what the other actor sends back

  2. abstract def askWithStatus[Res](f: ([StatusReply[Res]]) => M)(implicit timeout: Timeout): Future[Res]

    The same as but only for requests that result in a response of type akka.pattern.StatusReply.

    The same as but only for requests that result in a response of type . If the response is a the returned future is completed successfully with the wrapped response. If the status response is a the returned future will be failed with the exception in the error (normally a akka.pattern.StatusReply.ErrorMessage).

  3. abstract def entityId: String

    The identifier for the particular entity referenced by this EntityRef.

    The identifier for the particular entity referenced by this EntityRef.

    // given sharding, typeKey
sharding.entityRefFor(typeKey, "someId").entityId == "someId"  // always true
  4. abstract def tell(msg: M): Unit

    Send a message to the entity referenced by this EntityRef using *at-most-once* messaging semantics.

    Send a message to the entity referenced by this EntityRef using *at-most-once* messaging semantics.

    Example usage:

    val target: EntityRef[String] = ...
target.tell("Hello")
    Definition Classes
    → RecipientRef
  5. abstract def typeKey: EntityTypeKey[M]

    The EntityTypeKey associated with this EntityRef.

  6. abstract def dataCenter: Option[String]

    The specified datacenter of the incarnation of the particular entity referenced by this EntityRef, if a datacenter was specified.

    The specified datacenter of the incarnation of the particular entity referenced by this EntityRef, if a datacenter was specified.

    Annotations
    @deprecated
    Deprecated

    (Since version 2.10.0) Use Akka Distributed Cluster instead

Concrete Value Members

  1. def !(msg: M): Unit

    Send a message to the entity referenced by this EntityRef using *at-most-once* messaging semantics.

    Send a message to the entity referenced by this EntityRef using *at-most-once* messaging semantics.

    Example usage:

    val target: EntityRef[String] = ...
target ! "Hello"
  2. def ?[Res](message: (ActorRef[Res]) => M)(implicit timeout: Timeout): Future[Res]

    Allows to "ask" the EntityRef for a reply.

    Allows to "ask" the for a reply. See akka.actor.typed.scaladsl.AskPattern for a complete write-up of this pattern

    Note that if you are inside of an actor you should prefer akka.actor.typed.scaladsl.ActorContext.ask as that provides better safety.

    Example usage:

    case class Request(msg: String, replyTo: ActorRef[Reply])
case class Reply(msg: String)

implicit val timeout = Timeout(3.seconds)
val target: EntityRef[Request] = ...
val f: Future[Reply] = target ? (replyTo => Request("hello", replyTo))

    Please note that an implicit akka.util.Timeout must be available to use this pattern.

    Note: it is preferable to use the non-symbolic ask method as it easier allows for wildcards for the replyTo: ActorRef.

    Res

    The response protocol, what the other actor sends back

  3. val ref: RecipientRef[M]
    Implicit
    This member is added by an implicit conversion from EntityRef[M] toRecipientRefOps[M] performed by method RecipientRefOps in akka.actor.typed.RecipientRef.
    Definition Classes
    RecipientRefOps

Shadowed Implicit Value Members

  1. def !(msg: M): Unit

    Send a message to the destination referenced by this RecipientRef using *at-most-once* messaging semantics.

    Send a message to the destination referenced by this RecipientRef using *at-most-once* messaging semantics.

    Implicit
    This member is added by an implicit conversion from EntityRef[M] toRecipientRefOps[M] performed by method RecipientRefOps in akka.actor.typed.RecipientRef.
    Shadowing
    This implicitly inherited member is shadowed by one or more members in this class.
    To access this member you can use a type ascription:
    (entityRef: RecipientRefOps[M]).!(msg)
    Definition Classes
    RecipientRefOps