Scala 声称我正在使用不同版本的 Akka

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我正在组建一个小型 SBT 项目并学习如何使用 akka actor。我能够得到一个仅使用 akka 的简单示例，但是一旦我使用外部库，事情就会停止工作。我用这个得到了一个非常大的堆栈跟踪

objc[15196]: Class JavaLaunchHelper is implemented in both 
/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/bin/java (0x10cc6c4c0) and /Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home/jre/lib/libinstrument.dylib (0x10ccf84e0). One of the two will be used. Which one is undefined.
Detected java.lang.NoSuchMethodError error, which MAY be caused by incompatible Akka versions on the classpath. Please note that a given Akka version MUST be the same across all modules of Akka that you are using, e.g. if you use akka-actor [2.5.8 (resolved from current classpath)] all other core Akka modules MUST be of the same version. External projects like Alpakka, Persistence plugins or Akka HTTP etc. have their own version numbers - please make sure you're using a compatible set of libraries.                 
Uncaught error from thread [HelloSystem-akka.actor.default-dispatcher-4]: akka.actor.ActorCell.addFunctionRef(Lscala/Function2;)Lakka/actor/FunctionRef;, shutting down JVM since 'akka.jvm-exit-on-fatal-error' is enabled for for ActorSystem[HelloSystem]
java.lang.NoSuchMethodError: akka.actor.ActorCell.addFunctionRef(Lscala/Function2;)Lakka/actor/FunctionRef;

我的依赖项如下所示:

  object v {
    val akka = "2.5.8"
    val scrape = "0.4.0"
  }

  val akka = Seq(
    "com.typesafe.akka" %% "akka-actor" % v.akka,
    "com.typesafe.akka" %% "akka-slf4j" % v.akka
  )

  val scrape = Seq(
    "io.bfil" %% "scalescrape" % v.scrape
  )

  lazy val allDeps =  akka ++ scrape

我正在使用this library也使用 akka 版本 5.8 那么有什么好处呢？这个矛盾的 akka actor 版本是从哪里来的？这是我的 build.sbt，其中包括我尝试使用的冲突管理器:

import Dependencies._

name := "sputnik-scraper"

version := "0.1"

scalaVersion := "2.12.4"

conflictManager := ConflictManager.strict

dependencyOverrides += "com.typesafe.akka" %% "akka-actor" % "2.5.8"

lazy val root = (project in file(".")).settings(
  libraryDependencies ++= allDeps
)

编辑:添加了 main 中的代码。

import akka.actor.{ActorSystem, Props}
import io.bfil.scalescrape.actor.ScrapingActor

object Main extends App {

  val system = ActorSystem("HelloSystem")
  // default Actor constructor
  val helloActor = system.actorOf(Props[ExampleScraper], name = "helloactor")
  helloActor ! "hello"
  helloActor ! "buenos dias"
}


class ExampleScraper extends ScrapingActor {

  private val baseUrl = "https://www.sputnikmusic.com/"

  override def receive: Receive = {
    case _       => grabMainTitle(baseUrl)
  }

  private def grabMainTitle(url: String) =
    scrape {
          get(url) { response =>
            complete(doIt(response))
          }
    }

  private def doIt(response: Any): Unit = {
    println(response)
  }
}

Answer 1

很有可能是由 scalescrape 中使用的 Akka-HTTP 版本 10.0.1 引起的与 Akka 2.5 不同步。这是最新版本 Akka-HTTP 10.0.5 的发行说明:

This is the fifth maintenance release of the Akka HTTP 10.0 series. It is primarily aimed at stability aligning the internals with the upcoming Akka 2.5 release. ...

您可能需要考虑将 Akka-HTTP 依赖项修改为更新版本的 Akka HTTP 10.0。目前最新版本是 10.0.11。