akka

问题 This is by large combination of design and code problem. Use Case - Given many log files in range (2MB - 2GB), I need to parse each of these logs and apply some processing, generate Java POJO . - For this problem, lets assume that we have just 1 log file - Also, the idea is to making best use of System. Multiple cores are available. Alternative 1 - Open file (synchronous), read each line, generate POJO s FileActor -> read each line -> List<POJO> Pros : simple to understand Cons : Serial

问题 I am trying to get a simple Akka program building with Eclipse and Scala. I used g8 to create the sbt project with Akka(g8 typesafehub/akka-scala-sbt) and then sbteclispe to create the Eclipse project. When I import the project into Eclipse I'm given errors saying I am missing Akka. Is there any way that I can build an Akka project with Eclipse? 回答1: The simplest thing is to add the sbteclipse plugin to your Sbt build. It automatically generates project files for Eclipse, so that you can

问题 I know that it is not recommended to block in the receive method of an actor, but I believe it can be done (as long as it is not done in too many actors at once). This post suggests blocking in preStart as one way to solve a problem, so presumably blocking in preStart is safe. However, I tried to block in preRestart (not preStart ) and everything seemed to just hang - no more messages were logged as received. Also, in cases where it is not safe to block, what is a safe alternative? 回答1: It's

问题 I've an unexpected behavior when using remote actors. I've a server and a 'client'. The client sends a message to the server actor and the server replies. When I use the '?' operator everything works as expected. I get the answer back from the server. The server: class HelloWorldActor extends Actor { def receive = { case msg => self reply (msg + " World") } } object Server extends App{ Actor.remote.start("localhost",2552); Actor.remote.register("hello-service",Actor.actorOf[HelloWorldActor])

问题 I am trying my hands on the Akka Pi java tutorials I am trying to creaate a maven project as stated in the tutorial but any time I enter the command to create a maven project I get an error. Below are the command and the Error. C:\Program Files\akka-2.0.2>mvn archetype:generate \ C:\Program Files\akka-2.0.2>mvn archetype:generate \ [INFO] Scanning for projects... [INFO] ------------------------------------------------------------------------ [INFO] BUILD FAILURE [INFO] -----------------------

问题 I'm just starting to work with Akka and I can't decide if I should use dependency injection (like cake pattern) or actor lookup in order to decouple the actors from each others. What is the preferred method? 回答1: You should prefer to introduce actors to each other, which means to send an ActorRef in or with a message or to pass it into a constructor. The latter may involve the cake pattern of you so choose, but lookup is much more expensive and therefore you should use real ActorRef whenever

问题 I want to print logs on console and also write them in a file. In my scala project using akka loggers here is my build.sbt libraryDependencies ++= Seq("org.mongodb" %% "casbah" % "2.8.0", "org.slf4j" % "slf4j-simple" % "1.7.12", "org.elasticsearch" % "elasticsearch" % "1.5.0", "org.scalatest" %% "scalatest" % "2.2.1" % "test" withSources() withJavadoc(), "org.easymock" % "easymock" % "3.1" withSources() withJavadoc(), "org.mockito" % "mockito-all" % "1.9.5", "com.typesafe.akka" %% "akka-actor

问题 How do I make Akka aware of Play's logback config (application-logger.xml)? In my case it is completely ignored: The log is ONLY printed to stdout. I expect it to be logged to the File-Appender defined in application-logger.xml It does not make a difference if I rename application-logger.xml to logback.xml. Actor-class: class Dispatcher extends Actor with ActorLogging { // prints to stdout ONLY: log.error("[akka-logger] dispatch started...") } conf/application.conf: play { akka { #log-config

问题 Is there an idiomatic way of handling Akka stream's Source first element in a special way? What I have now is: var firstHandled = false source.map { elem => if(!firstHandled) { //handle specially firstHandled = true } else { //handle normally } } Thanks 回答1: While I would generally go with Ramon's answer, you could also use prefixAndTail, with a prefix of 1, together with flatMapConcat to achieve something similar: val src = Source(List(1, 2, 3, 4, 5)) val fst = Flow[Int].map(i => s"First: $i

问题 I'm running into a problem with an actor that extends Stash and which works perfectly fine when instantiating it with actorOf in a simple ActorSystem. Now I would actually like to write some tests for my stashing actors before using them in my program. But I cannot figure out a way to use an TestActorRef with this actor in my test suite. The code that works looks like this: import akka.actor.{Stash, Actor, ActorSystem, Props} import com.typesafe.config.ConfigFactory object StashTest { val