Package akka.pattern

Class Patterns$

  • public class Patterns$
extends java.lang.Object
    Java API: for Akka patterns such as ask, pipe and others which work with CompletionStage.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static Patterns$ MODULE$
      Static reference to the singleton instance of this Scala object.

    • Constructor Summary

      Constructors 
      Constructor Description
      Patterns$()  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      <T> java.util.concurrent.CompletionStage<T> after​(java.time.Duration duration, ClassicActorSystemProvider system, java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> value)
      Returns a CompletionStage that will be completed with the success or failure of the provided Callable after the specified duration.
      <T> java.util.concurrent.CompletionStage<T> after​(java.time.Duration duration, Scheduler scheduler, scala.concurrent.ExecutionContext context, java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> value)
      Returns a CompletionStage that will be completed with the success or failure of the provided Callable after the specified duration.
      <T> scala.concurrent.Future<T> after​(scala.concurrent.duration.FiniteDuration duration, Scheduler scheduler, scala.concurrent.ExecutionContext context, java.util.concurrent.Callable<scala.concurrent.Future<T>> value)
      Returns a Future that will be completed with the success or failure of the provided Callable after the specified duration.
      scala.concurrent.Future<java.lang.Object> ask​(ActorRef actor, java.lang.Object message, long timeoutMillis)
      Java API for akka.pattern.ask: Sends a message asynchronously and returns a Future holding the eventual reply message; this means that the target actor needs to send the result to the sender reference provided.
      scala.concurrent.Future<java.lang.Object> ask​(ActorRef actor, java.lang.Object message, Timeout timeout)
      Java API for akka.pattern.ask: Sends a message asynchronously and returns a Future holding the eventual reply message; this means that the target actor needs to send the result to the sender reference provided.
      java.util.concurrent.CompletionStage<java.lang.Object> ask​(ActorRef actor, java.lang.Object message, java.time.Duration timeout)
      Java API for akka.pattern.ask: Sends a message asynchronously and returns a CompletionStage holding the eventual reply message; this means that the target actor needs to send the result to the sender reference provided.
      scala.concurrent.Future<java.lang.Object> ask​(ActorSelection selection, java.lang.Object message, long timeoutMillis)
      Java API for akka.pattern.ask: Sends a message asynchronously and returns a Future holding the eventual reply message; this means that the target ActorSelection needs to send the result to the sender reference provided.
      scala.concurrent.Future<java.lang.Object> ask​(ActorSelection selection, java.lang.Object message, Timeout timeout)
      Java API for akka.pattern.ask: Sends a message asynchronously and returns a Future holding the eventual reply message; this means that the target ActorSelection needs to send the result to the sender reference provided.
      java.util.concurrent.CompletionStage<java.lang.Object> ask​(ActorSelection selection, java.lang.Object message, java.time.Duration timeout)
      Java API for akka.pattern.ask: Sends a message asynchronously and returns a CompletionStage holding the eventual reply message; this means that the target ActorSelection needs to send the result to the sender reference provided.
      java.util.concurrent.CompletionStage<java.lang.Object> askWithReplyTo​(ActorRef actor, Function<ActorRef,​java.lang.Object> messageFactory, java.time.Duration timeout)
      A variation of ask which allows to implement "replyTo" pattern by including sender reference in message.
      scala.concurrent.Future<java.lang.Object> askWithReplyTo​(ActorRef actor, Function<ActorRef,​java.lang.Object> messageFactory, long timeoutMillis)
      A variation of ask which allows to implement "replyTo" pattern by including sender reference in message.
      scala.concurrent.Future<java.lang.Object> askWithReplyTo​(ActorRef actor, Function<ActorRef,​java.lang.Object> messageFactory, Timeout timeout)
      A variation of ask which allows to implement "replyTo" pattern by including sender reference in message.
      scala.concurrent.Future<java.lang.Object> askWithReplyTo​(ActorSelection selection, Function<ActorRef,​java.lang.Object> messageFactory, long timeoutMillis)
      A variation of ask which allows to implement "replyTo" pattern by including sender reference in message.
      java.util.concurrent.CompletionStage<java.lang.Object> askWithReplyTo​(ActorSelection selection, Function<ActorRef,​java.lang.Object> messageFactory, java.time.Duration timeout)
      A variation of ask which allows to implement "replyTo" pattern by including sender reference in message.
      java.util.concurrent.CompletionStage<java.lang.Object> askWithStatus​(ActorRef actor, java.lang.Object message, java.time.Duration timeout)
      Use for messages whose response is known to be a StatusReply.
      java.time.Duration calculateExponentialBackoffDelay​(int attempt, java.time.Duration minBackoff, java.time.Duration maxBackoff, double randomFactor)
      Calculates an exponential back off delay.
      java.util.concurrent.CompletionStage<java.lang.Boolean> gracefulStop​(ActorRef target, java.time.Duration timeout)
      Returns a CompletionStage that will be completed with success (value true) when existing messages of the target actor has been processed and the actor has been terminated.
      java.util.concurrent.CompletionStage<java.lang.Boolean> gracefulStop​(ActorRef target, java.time.Duration timeout, java.lang.Object stopMessage)
      Returns a CompletionStage that will be completed with success (value true) when existing messages of the target actor has been processed and the actor has been terminated.
      scala.concurrent.Future<java.lang.Boolean> gracefulStop​(ActorRef target, scala.concurrent.duration.FiniteDuration timeout)
      Returns a Future that will be completed with success (value true) when existing messages of the target actor has been processed and the actor has been terminated.
      scala.concurrent.Future<java.lang.Boolean> gracefulStop​(ActorRef target, scala.concurrent.duration.FiniteDuration timeout, java.lang.Object stopMessage)
      Returns a Future that will be completed with success (value true) when existing messages of the target actor has been processed and the actor has been terminated.
      <T> PipeToSupport.PipeableCompletionStage<T> pipe​(java.util.concurrent.CompletionStage<T> future, scala.concurrent.ExecutionContext context)
      When this CompletionStage finishes, send its result to the given ActorRef or ActorSelection.
      <T> PipeToSupport.PipeableFuture<T> pipe​(scala.concurrent.Future<T> future, scala.concurrent.ExecutionContext context)
      Register an onComplete callback on this Future to send the result to the given ActorRef or ActorSelection.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, int attempts, java.time.Duration delay, ClassicActorSystemProvider system)
      Returns an internally retrying CompletionStage The first attempt will be made immediately, and each subsequent attempt will be made after 'delay'.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, int attempts, java.time.Duration delay, Scheduler scheduler, scala.concurrent.ExecutionContext ec)
      Returns an internally retrying CompletionStage The first attempt will be made immediately, and each subsequent attempt will be made after 'delay'.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, int attempts, java.time.Duration minBackoff, java.time.Duration maxBackoff, double randomFactor, ClassicActorSystemProvider system)
      Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made with a backoff time, if the previous attempt failed.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, int attempts, java.time.Duration minBackoff, java.time.Duration maxBackoff, double randomFactor, Scheduler scheduler, scala.concurrent.ExecutionContext ec)
      Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made with a backoff time, if the previous attempt failed.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, int attempts, java.time.Duration minBackoff, java.time.Duration maxBackoff, double randomFactor, java.util.function.Predicate<java.lang.Throwable> shouldRetry, ClassicActorSystemProvider system)
      Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made with a backoff time if the preceding attempt failed and the provided predicate tests true for the failure's exception.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, int attempts, java.time.Duration minBackoff, java.time.Duration maxBackoff, double randomFactor, java.util.function.Predicate<java.lang.Throwable> shouldRetry, Scheduler scheduler, scala.concurrent.ExecutionContext ec)
      Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made with a backoff time if the preceding attempt failed and the provided predicate tests true for the failure's exception.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, int attempts, java.util.function.IntFunction<java.util.Optional<java.time.Duration>> delayFunction, Scheduler scheduler, scala.concurrent.ExecutionContext context)
      Returns an internally retrying CompletionStage.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, int attempts, java.util.function.IntFunction<java.util.Optional<java.time.Duration>> delayFunction, java.util.function.Predicate<java.lang.Throwable> shouldRetry, Scheduler scheduler, scala.concurrent.ExecutionContext context)
      Returns an internally retrying CompletionStage The first attempt will be made immediately, any subsequent attempt will be made after the delay returned by the delay function (which can return an empty Optional for an immediate retry; it must never return null).
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, int attempts, scala.concurrent.ExecutionContext ec)
      Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made immediately if the previous attempt failed.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, RetrySettings retrySettings, ClassicActorSystemProvider system)
      Returns an internally retrying CompletionStage.
      <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt, java.util.function.Predicate<java.lang.Throwable> shouldRetry, int attempts, scala.concurrent.ExecutionContext ec)
      Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made immediately if the previous attempt failed and the provided predicate tests true for the failure's exception.
      <T> scala.concurrent.Future<T> retry​(java.util.concurrent.Callable<scala.concurrent.Future<T>> attempt, int attempts, scala.concurrent.duration.FiniteDuration delay, Scheduler scheduler, scala.concurrent.ExecutionContext context)
      Returns an internally retrying Future The first attempt will be made immediately, and each subsequent attempt will be made after 'delay'.

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • MODULE$

        public static final Patterns$ MODULE$
        Static reference to the singleton instance of this Scala object.

    • Constructor Detail

      • Patterns$

        public Patterns$()

    • Method Detail

      • ask

        public scala.concurrent.Future<java.lang.Object> ask​(ActorRef actor,
                                                     java.lang.Object message,
                                                     Timeout timeout)
        Java API for akka.pattern.ask: Sends a message asynchronously and returns a Future holding the eventual reply message; this means that the target actor needs to send the result to the sender reference provided.

        The Future will be completed with an AskTimeoutException after the given timeout has expired; this is independent from any timeout applied while awaiting a result for this future (i.e. in Await.result(..., timeout)). A typical reason for AskTimeoutException is that the recipient actor didn't send a reply.

        Warning: When using future callbacks, inside actors you need to carefully avoid closing over the containing actor&rsquo;s object, i.e. do not call methods or access mutable state on the enclosing actor from within the callback. This would break the actor encapsulation and may introduce synchronization bugs and race conditions because the callback will be scheduled concurrently to the enclosing actor. Unfortunately there is not yet a way to detect these illegal accesses at compile time.

        Recommended usage: 

        
   final Future<Object> f = Patterns.ask(worker, request, timeout);
   f.onSuccess(new Procedure<Object>() {
     public void apply(Object o) {
       nextActor.tell(new EnrichedResult(request, o));
     }
   });

      • ask

        public java.util.concurrent.CompletionStage<java.lang.Object> ask​(ActorRef actor,
                                                                  java.lang.Object message,
                                                                  java.time.Duration timeout)
        Java API for akka.pattern.ask: Sends a message asynchronously and returns a CompletionStage holding the eventual reply message; this means that the target actor needs to send the result to the sender reference provided.

        The CompletionStage will be completed with an AskTimeoutException after the given timeout has expired; this is independent from any timeout applied while awaiting a result for this future (i.e. in Await.result(..., timeout)). A typical reason for AskTimeoutException is that the recipient actor didn't send a reply.

        Warning: When using future callbacks, inside actors you need to carefully avoid closing over the containing actor&rsquo;s object, i.e. do not call methods or access mutable state on the enclosing actor from within the callback. This would break the actor encapsulation and may introduce synchronization bugs and race conditions because the callback will be scheduled concurrently to the enclosing actor. Unfortunately there is not yet a way to detect these illegal accesses at compile time.

        Recommended usage: 

        
   final CompletionStage<Object> f = Patterns.ask(worker, request, duration);
   f.thenRun(result -> nextActor.tell(new EnrichedResult(request, result)));

      • askWithStatus

        public java.util.concurrent.CompletionStage<java.lang.Object> askWithStatus​(ActorRef actor,
                                                                            java.lang.Object message,
                                                                            java.time.Duration timeout)
        Use for messages whose response is known to be a StatusReply. When a StatusReply.success(T) response arrives the future is completed with the wrapped value, if a StatusReply.error(java.lang.String) arrives the future is instead failed.

      • askWithReplyTo

        public scala.concurrent.Future<java.lang.Object> askWithReplyTo​(ActorRef actor,
                                                                Function<ActorRef,​java.lang.Object> messageFactory,
                                                                Timeout timeout)
        A variation of ask which allows to implement "replyTo" pattern by including sender reference in message. 

        
 final Future<Object> f = Patterns.askWithReplyTo(
   worker,
   replyTo -> new Request(replyTo),
   timeout);

      • askWithReplyTo

        public java.util.concurrent.CompletionStage<java.lang.Object> askWithReplyTo​(ActorRef actor,
                                                                             Function<ActorRef,​java.lang.Object> messageFactory,
                                                                             java.time.Duration timeout)
        A variation of ask which allows to implement "replyTo" pattern by including sender reference in message. 

        
 final CompletionStage<Object> f = Patterns.askWithReplyTo(
   worker,
   askSender -> new Request(askSender),
   timeout);

        Parameters:
        actor - the actor to be asked
        messageFactory - function taking an actor ref and returning the message to be sent
        timeout - the timeout for the response before failing the returned completion stage

      • ask

        public scala.concurrent.Future<java.lang.Object> ask​(ActorRef actor,
                                                     java.lang.Object message,
                                                     long timeoutMillis)
        Java API for akka.pattern.ask: Sends a message asynchronously and returns a Future holding the eventual reply message; this means that the target actor needs to send the result to the sender reference provided.

        The Future will be completed with an AskTimeoutException after the given timeout has expired; this is independent from any timeout applied while awaiting a result for this future (i.e. in Await.result(..., timeout)). A typical reason for AskTimeoutException is that the recipient actor didn't send a reply.

        Warning: When using future callbacks, inside actors you need to carefully avoid closing over the containing actor&rsquo;s object, i.e. do not call methods or access mutable state on the enclosing actor from within the callback. This would break the actor encapsulation and may introduce synchronization bugs and race conditions because the callback will be scheduled concurrently to the enclosing actor. Unfortunately there is not yet a way to detect these illegal accesses at compile time.

        Recommended usage: 

        
   final Future<Object> f = Patterns.ask(worker, request, timeout);
   f.onSuccess(new Procedure<Object>() {
     public void apply(Object o) {
       nextActor.tell(new EnrichedResult(request, o));
     }
   });

      • askWithReplyTo

        public scala.concurrent.Future<java.lang.Object> askWithReplyTo​(ActorRef actor,
                                                                Function<ActorRef,​java.lang.Object> messageFactory,
                                                                long timeoutMillis)
        A variation of ask which allows to implement "replyTo" pattern by including sender reference in message. 

        
 final Future<Object> f = Patterns.askWithReplyTo(
   worker,
   replyTo -> new Request(replyTo),
   timeout);

      • ask

        public scala.concurrent.Future<java.lang.Object> ask​(ActorSelection selection,
                                                     java.lang.Object message,
                                                     Timeout timeout)
        Java API for akka.pattern.ask: Sends a message asynchronously and returns a Future holding the eventual reply message; this means that the target ActorSelection needs to send the result to the sender reference provided.

        The Future will be completed with an AskTimeoutException after the given timeout has expired; this is independent from any timeout applied while awaiting a result for this future (i.e. in Await.result(..., timeout)). A typical reason for AskTimeoutException is that the recipient actor didn't send a reply.

        Warning: When using future callbacks, inside actors you need to carefully avoid closing over the containing actor&rsquo;s object, i.e. do not call methods or access mutable state on the enclosing actor from within the callback. This would break the actor encapsulation and may introduce synchronization bugs and race conditions because the callback will be scheduled concurrently to the enclosing actor. Unfortunately there is not yet a way to detect these illegal accesses at compile time.

        Recommended usage: 

        
   final Future<Object> f = Patterns.ask(selection, request, timeout);
   f.onSuccess(new Procedure<Object>() {
     public void apply(Object o) {
       nextActor.tell(new EnrichedResult(request, o));
     }
   });

      • ask

        public java.util.concurrent.CompletionStage<java.lang.Object> ask​(ActorSelection selection,
                                                                  java.lang.Object message,
                                                                  java.time.Duration timeout)
        Java API for akka.pattern.ask: Sends a message asynchronously and returns a CompletionStage holding the eventual reply message; this means that the target ActorSelection needs to send the result to the sender reference provided.

        The CompletionStage will be completed with an AskTimeoutException after the given timeout has expired; this is independent from any timeout applied while awaiting a result for this future (i.e. in Await.result(..., timeout)). A typical reason for AskTimeoutException is that the recipient actor didn't send a reply.

        Warning: When using future callbacks, inside actors you need to carefully avoid closing over the containing actor&rsquo;s object, i.e. do not call methods or access mutable state on the enclosing actor from within the callback. This would break the actor encapsulation and may introduce synchronization bugs and race conditions because the callback will be scheduled concurrently to the enclosing actor. Unfortunately there is not yet a way to detect these illegal accesses at compile time.

        Recommended usage: 

        
   final CompletionStage<Object> f = Patterns.ask(selection, request, duration);
   f.thenRun(result -> nextActor.tell(new EnrichedResult(request, result)));

      • ask

        public scala.concurrent.Future<java.lang.Object> ask​(ActorSelection selection,
                                                     java.lang.Object message,
                                                     long timeoutMillis)
        Java API for akka.pattern.ask: Sends a message asynchronously and returns a Future holding the eventual reply message; this means that the target ActorSelection needs to send the result to the sender reference provided.

        The Future will be completed with an AskTimeoutException after the given timeout has expired; this is independent from any timeout applied while awaiting a result for this future (i.e. in Await.result(..., timeout)). A typical reason for AskTimeoutException is that the recipient actor didn't send a reply.

        Warning: When using future callbacks, inside actors you need to carefully avoid closing over the containing actor&rsquo;s object, i.e. do not call methods or access mutable state on the enclosing actor from within the callback. This would break the actor encapsulation and may introduce synchronization bugs and race conditions because the callback will be scheduled concurrently to the enclosing actor. Unfortunately there is not yet a way to detect these illegal accesses at compile time.

        Recommended usage: 

        
   final Future<Object> f = Patterns.ask(selection, request, timeout);
   f.onSuccess(new Procedure<Object>() {
     public void apply(Object o) {
       nextActor.tell(new EnrichedResult(request, o));
     }
   });

      • askWithReplyTo

        public scala.concurrent.Future<java.lang.Object> askWithReplyTo​(ActorSelection selection,
                                                                Function<ActorRef,​java.lang.Object> messageFactory,
                                                                long timeoutMillis)
        A variation of ask which allows to implement "replyTo" pattern by including sender reference in message. 

        
 final Future<Object> f = Patterns.askWithReplyTo(
   selection,
   replyTo -> new Request(replyTo),
   timeout);

      • askWithReplyTo

        public java.util.concurrent.CompletionStage<java.lang.Object> askWithReplyTo​(ActorSelection selection,
                                                                             Function<ActorRef,​java.lang.Object> messageFactory,
                                                                             java.time.Duration timeout)
        A variation of ask which allows to implement "replyTo" pattern by including sender reference in message. 

        
 final CompletionStage<Object> f = Patterns.askWithReplyTo(
   selection,
   replyTo -> new Request(replyTo),
   timeout);

      • pipe

        public <T> PipeToSupport.PipeableFuture<T> pipe​(scala.concurrent.Future<T> future,
                                                scala.concurrent.ExecutionContext context)
        Register an onComplete callback on this Future to send the result to the given ActorRef or ActorSelection. Returns the original Future to allow method chaining. If the future was completed with failure it is sent as a Status.Failure to the recipient.

        Recommended usage example: 

        
   final Future<Object> f = Patterns.ask(worker, request, timeout);
   // apply some transformation (i.e. enrich with request info)
   final Future<Object> transformed = f.map(new akka.japi.Function<Object, Object>() { ... });
   // send it on to the next operator
   Patterns.pipe(transformed, context).to(nextActor);

      • pipe

        public <T> PipeToSupport.PipeableCompletionStage<T> pipe​(java.util.concurrent.CompletionStage<T> future,
                                                         scala.concurrent.ExecutionContext context)
        When this CompletionStage finishes, send its result to the given ActorRef or ActorSelection. Returns the original CompletionStage to allow method chaining. If the future was completed with failure it is sent as a Status.Failure to the recipient.

        Recommended usage example: 

        
   final CompletionStage<Object> f = Patterns.ask(worker, request, timeout);
   // apply some transformation (i.e. enrich with request info)
   final CompletionStage<Object> transformed = f.thenApply(result -> { ... });
   // send it on to the next operator
   Patterns.pipe(transformed, context).to(nextActor);

      • gracefulStop

        public scala.concurrent.Future<java.lang.Boolean> gracefulStop​(ActorRef target,
                                                               scala.concurrent.duration.FiniteDuration timeout)
        Returns a Future that will be completed with success (value true) when existing messages of the target actor has been processed and the actor has been terminated.

        Useful when you need to wait for termination or compose ordered termination of several actors.

        If the target actor isn't terminated within the timeout the Future is completed with failure AskTimeoutException.

      • gracefulStop

        public java.util.concurrent.CompletionStage<java.lang.Boolean> gracefulStop​(ActorRef target,
                                                                            java.time.Duration timeout)
        Returns a CompletionStage that will be completed with success (value true) when existing messages of the target actor has been processed and the actor has been terminated.

        Useful when you need to wait for termination or compose ordered termination of several actors.

        If the target actor isn't terminated within the timeout the CompletionStage is completed with failure AskTimeoutException.

      • gracefulStop

        public scala.concurrent.Future<java.lang.Boolean> gracefulStop​(ActorRef target,
                                                               scala.concurrent.duration.FiniteDuration timeout,
                                                               java.lang.Object stopMessage)
        Returns a Future that will be completed with success (value true) when existing messages of the target actor has been processed and the actor has been terminated.

        Useful when you need to wait for termination or compose ordered termination of several actors.

        If you want to invoke specialized stopping logic on your target actor instead of PoisonPill, you can pass your stop command as stopMessage parameter

        If the target actor isn't terminated within the timeout the Future is completed with failure AskTimeoutException.

      • gracefulStop

        public java.util.concurrent.CompletionStage<java.lang.Boolean> gracefulStop​(ActorRef target,
                                                                            java.time.Duration timeout,
                                                                            java.lang.Object stopMessage)
        Returns a CompletionStage that will be completed with success (value true) when existing messages of the target actor has been processed and the actor has been terminated.

        Useful when you need to wait for termination or compose ordered termination of several actors.

        If you want to invoke specialized stopping logic on your target actor instead of PoisonPill, you can pass your stop command as stopMessage parameter

        If the target actor isn't terminated within the timeout the CompletionStage is completed with failure AskTimeoutException.

      • after

        public <T> scala.concurrent.Future<T> after​(scala.concurrent.duration.FiniteDuration duration,
                                            Scheduler scheduler,
                                            scala.concurrent.ExecutionContext context,
                                            java.util.concurrent.Callable<scala.concurrent.Future<T>> value)
        Returns a Future that will be completed with the success or failure of the provided Callable after the specified duration.

      • after

        public <T> java.util.concurrent.CompletionStage<T> after​(java.time.Duration duration,
                                                         ClassicActorSystemProvider system,
                                                         java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> value)
        Returns a CompletionStage that will be completed with the success or failure of the provided Callable after the specified duration.

      • after

        public <T> java.util.concurrent.CompletionStage<T> after​(java.time.Duration duration,
                                                         Scheduler scheduler,
                                                         scala.concurrent.ExecutionContext context,
                                                         java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> value)
        Returns a CompletionStage that will be completed with the success or failure of the provided Callable after the specified duration.

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         int attempts,
                                                         scala.concurrent.ExecutionContext ec)
        Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made immediately if the previous attempt failed.

        If attempts are exhausted the returned completion CompletionStage is simply the result of invoking attempt. Note that the attempt function will be invoked on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         java.util.function.Predicate<java.lang.Throwable> shouldRetry,
                                                         int attempts,
                                                         scala.concurrent.ExecutionContext ec)
        Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made immediately if the previous attempt failed and the provided predicate tests true for the failure's exception. If the predicate tests false, the failed attempt will be returned. This allows for short-circuiting in situations where the retries cannot be expected to succeed (e.g. in a situation where the legality of arguments can only be determined asynchronously).

        If attempts are exhausted, the returned CompletionStage is that of the last attempt. Note that the attempt function will be executed on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         int attempts,
                                                         java.time.Duration minBackoff,
                                                         java.time.Duration maxBackoff,
                                                         double randomFactor,
                                                         ClassicActorSystemProvider system)
        Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made with a backoff time, if the previous attempt failed.

        If attempts are exhausted the returned future is simply the result of invoking attempt. Note that the attempt function will be invoked on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

        Parameters:
        minBackoff - minimum (initial) duration until the child actor will started again, if it is terminated
        maxBackoff - the exponential back-off is capped to this duration
        randomFactor - after calculation of the exponential back-off an additional random delay based on this factor is added, e.g. 0.2 adds up to 20% delay. In order to skip this additional delay pass in 0.

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         int attempts,
                                                         java.time.Duration minBackoff,
                                                         java.time.Duration maxBackoff,
                                                         double randomFactor,
                                                         java.util.function.Predicate<java.lang.Throwable> shouldRetry,
                                                         ClassicActorSystemProvider system)
        Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made with a backoff time if the preceding attempt failed and the provided predicate tests true for the failure's exception. If the predicate tests false, the failed attempt will be returned. This allows for short-circuiting in situations where the retries cannot be expected to succeed (e.g. in a situation where the legality of arguments can only be determined asynchronously).

        If attempts are exhausted, the returned CompletionStage is that of the last attempt. Note that the attempt function will be executed on the actor system's dispatcher for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         int attempts,
                                                         java.time.Duration minBackoff,
                                                         java.time.Duration maxBackoff,
                                                         double randomFactor,
                                                         Scheduler scheduler,
                                                         scala.concurrent.ExecutionContext ec)
        Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made with a backoff time, if the previous attempt failed.

        If attempts are exhausted the returned future is simply the result of invoking attempt. Note that the attempt function will be invoked on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

        Parameters:
        minBackoff - minimum (initial) duration until the attempt will be retried
        maxBackoff - the exponential back-off is capped to this duration
        randomFactor - after calculation of the exponential back-off an additional random delay based on this factor is added, e.g. 0.2 adds up to 20% delay. In order to skip this additional delay pass in 0.

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         int attempts,
                                                         java.time.Duration minBackoff,
                                                         java.time.Duration maxBackoff,
                                                         double randomFactor,
                                                         java.util.function.Predicate<java.lang.Throwable> shouldRetry,
                                                         Scheduler scheduler,
                                                         scala.concurrent.ExecutionContext ec)
        Returns an internally retrying CompletionStage The first attempt will be made immediately, each subsequent attempt will be made with a backoff time if the preceding attempt failed and the provided predicate tests true for the failure's exception. If the predicate tests false, the failed attempt will be returned. This allows for short-circuiting in situations where the retries cannot be expected to succeed (e.g. in a situation where the legality of arguments can only be determined asynchronously).

        If attempts are exhausted, the returned CompletionStage is that of the last attempt. Note that the attempt function will be executed on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

      • retry

        public <T> scala.concurrent.Future<T> retry​(java.util.concurrent.Callable<scala.concurrent.Future<T>> attempt,
                                            int attempts,
                                            scala.concurrent.duration.FiniteDuration delay,
                                            Scheduler scheduler,
                                            scala.concurrent.ExecutionContext context)
        Returns an internally retrying Future The first attempt will be made immediately, and each subsequent attempt will be made after 'delay'. A scheduler (eg context.system.scheduler) must be provided to delay each retry

        If attempts are exhausted the returned future is simply the result of invoking attempt. Note that the attempt function will be invoked on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         int attempts,
                                                         java.time.Duration delay,
                                                         ClassicActorSystemProvider system)
        Returns an internally retrying CompletionStage The first attempt will be made immediately, and each subsequent attempt will be made after 'delay'. A scheduler (eg context.system.scheduler) must be provided to delay each retry

        If attempts are exhausted the returned CompletionStage is simply the result of invoking attempt. Note that the attempt function will be invoked on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         int attempts,
                                                         java.time.Duration delay,
                                                         Scheduler scheduler,
                                                         scala.concurrent.ExecutionContext ec)
        Returns an internally retrying CompletionStage The first attempt will be made immediately, and each subsequent attempt will be made after 'delay'. A scheduler (eg context.system.scheduler) must be provided to delay each retry

        If attempts are exhausted the returned CompletionStage is simply the result of invoking attempt. Note that the attempt function will be invoked on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         int attempts,
                                                         java.util.function.IntFunction<java.util.Optional<java.time.Duration>> delayFunction,
                                                         Scheduler scheduler,
                                                         scala.concurrent.ExecutionContext context)
        Returns an internally retrying CompletionStage. The first attempt will be made immediately, each subsequent attempt will be made after the 'delay' return by delayFunction(the input next attempt count start from 1). Return an empty Optional instance for no delay. A scheduler (eg context.system.scheduler) must be provided to delay each retry. You could provide a function to generate the next delay duration after first attempt, this function should never return null, otherwise an IllegalArgumentException will be through.

        If attempts are exhausted the returned future is simply the result of invoking attempt. Note that the attempt function will be invoked on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         int attempts,
                                                         java.util.function.IntFunction<java.util.Optional<java.time.Duration>> delayFunction,
                                                         java.util.function.Predicate<java.lang.Throwable> shouldRetry,
                                                         Scheduler scheduler,
                                                         scala.concurrent.ExecutionContext context)
        Returns an internally retrying CompletionStage The first attempt will be made immediately, any subsequent attempt will be made after the delay returned by the delay function (which can return an empty Optional for an immediate retry; it must never return null). A scheduler (e.g. context.system().scheduler()) must be provided to delay retries.

        If attempts are exhausted, the returned CompletionStage is that of the last attempt. Note that the attempt function will be invoked on the given execution context for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

        If an attempt fails, the exception from the failure will be tested with the provided predicate; if that predicate tests true, a retry will be attempted, if false, the most recent failure is returned. This allows for short-circuiting in situations where the retries cannot be expected to succeed (e.g. in a situation where the legality of arguments can only be determined asynchronously).

      • retry

        public <T> java.util.concurrent.CompletionStage<T> retry​(java.util.concurrent.Callable<java.util.concurrent.CompletionStage<T>> attempt,
                                                         RetrySettings retrySettings,
                                                         ClassicActorSystemProvider system)
        Returns an internally retrying CompletionStage. The first attempt will be made immediately, each subsequent attempt will be made based on the provided RetrySettings.

        If attempts are exhausted, the returned CompletionStage is that of the last attempt. Note that the attempt function will be executed on the actor system's dispatcher for subsequent tries and therefore must be thread safe (not touch unsafe mutable state).

      • calculateExponentialBackoffDelay

        public java.time.Duration calculateExponentialBackoffDelay​(int attempt,
                                                           java.time.Duration minBackoff,
                                                           java.time.Duration maxBackoff,
                                                           double randomFactor)
        Calculates an exponential back off delay.