我一直在关注QuickStart guide for Akka Streams,我遇到了一个错误 . 我的代码很简单:
object Main extends App {
implicit val system = ActorSystem("QuickStart")
implicit val materializer = ActorMaterializer()
val source: Source[Int, NotUsed] = Source(1 to 100)
source.runForeach(i => println(i)) (materializer)
}
但是这会导致错误:
线程“main”java.lang.NoClassDefFoundError中的异常:akka.util.Timeout中的scala / Product $ class . (Timeout.scala:13)akka.actor.ActorSystem $ Settings . (ActorSystem.scala:179)at akka .actor.ActorSystemImpl . (ActorSystem.scala:530)atkka.actor.ActorSystem $ .apply(ActorSystem.scala:142)atkka.actor.ActorSystem $ .apply(ActorSystem.scala:109)at streams_test.Main $ . delayedEndpoint $ streams_test $ Main $ 1(Main.scala:14)at streams_test.Main $ delayedInit $ body.apply(Main.scala:13)at scala.runtime.AbstractFunction0.apply $ mcV $ sp(AbstractFunction0.scala:12)at at scala.App . $ anonfun $ main $ 1 $ adapt(App.scala:76)at scala.collection.immutable.List.foreach(List.scala:378)scala.App.main(App.scala:76)at scala .App.main $(App.scala:74)at streams_test.Main $ .main(Main.scala:13)at streams_test.Main.main(Main.scala)at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)at at在sun.reflect.DelegatingMethodAccessorImpl.inv的sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) oke(DelegatingMethodAccessorImpl.java:43)at java.lang.reflect.Method.invoke(Method.java:498)at com.intellij.rt.execution.application.AppMain.main(AppMain.java:147)引起:java .lang.ClassNotFoundException:scala.Product $ class at java.net.URLClassLoader.findClass(URLClassLoader.java:381)at java.lang.ClassLoader.loadClass(ClassLoader.java:424)at sun.misc.Launcher $ AppClassLoader.loadClass (Launcher.java:331)java.lang.ClassLoader.loadClass(ClassLoader.java:357)... 19更多
我也试过通过sbt控制台运行它没有运气 . 有谁知道是什么导致了这个问题?它正在被抛弃:
implicit val system = ActorSystem("QuickStart")
根据要求,我的 build.sbt
文件:
name := "Akka_test"
version := "1.0"
scalaVersion := "2.12.0"
// https://mvnrepository.com/artifact/com.typesafe.akka/akka-actor_2.11
libraryDependencies += "com.typesafe.akka" % "akka-actor_2.11" % "2.3.9"
// https://mvnrepository.com/artifact/com.typesafe.akka/akka-stream_2.11
libraryDependencies += "com.typesafe.akka" % "akka-stream_2.11" % "2.4.12"
// https://mvnrepository.com/artifact/org.twitter4j/twitter4j-core
libraryDependencies += "org.twitter4j" % "twitter4j-core" % "4.0.2"
1 回答
这可能是您可能使用2.11编译库和2.11编译器的Scala版本问题,反之亦然 .
如果在build.sbt中明确包含scala版本并在build.sbt中的groupId之后使用
%%
,则可以避免遇到此问题用这个
代替