我在 IntelliJ 中从头开始的第一个 Akka 项目。编译依赖错误。

Question

我时不时地从头开始，以确保我知道设置项目的所有复杂细节是什么。我有一个像下面这样的简单应用程序，但我遇到了一些似乎并没有指向任何地方的依赖问题。我正在使用 scala 版本 2.11。

我的 SBT：

name := "Helios"

version := "1.0"

scalaVersion := "2.11.8"

resolvers += "Typesafe Repository" at "http://repo.typesafe.com/typesafe/releases/"

libraryDependencies ++= Seq(
  "com.typesafe.akka" % "akka-actor" % "2.0.2",
  "com.typesafe.akka" % "akka-slf4j" % "2.0.5")

我的示例类

import com.echostar.ese.helios.core.Asset
import akka.actor._

class NSPSG extends Actor {

  def receive = {
    case a: Asset => {
      println(s"NSPSG Received asset: ${a}")
    }
    case _ => println("Unexpected message received")
  }
}

（资产类只是一个案例类，里面有id和title。）

错误信息：

C:\PROJECTS\active\Helios>sbt compile
Java HotSpot(TM) 64-Bit Server VM warning: ignoring option MaxPermSize=256m; support was removed in 8.0
[info] Loading global plugins from C:\Users\dana.murad\.sbt\0.13\plugins
[info] Loading project definition from C:\PROJECTS\active\Helios\project
[info] Set current project to Helios (in build file:/C:/PROJECTS/active/Helios/)
[info] Updating {file:/C:/PROJECTS/active/Helios/}helios...
[info] Resolving jline#jline;2.12.1 ...
[info] Done updating.
[info] Compiling 3 Scala sources to C:\PROJECTS\active\Helios\target\scala-2.11\classes...
[error] missing or invalid dependency detected while loading class file 'package.class'.
[error] Could not access type ScalaObject in package scala,
[error] because it (or its dependencies) are missing. Check your build definition for
[error] missing or conflicting dependencies. (Re-run with `-Ylog-classpath` to see the problematic classpath.)
[error] A full rebuild may help if 'package.class' was compiled against an incompatible version of scala.
[error] missing or invalid dependency detected while loading class file 'Actor.class'.
[error] Could not access type ScalaObject in package scala,
[error] because it (or its dependencies) are missing. Check your build definition for
[error] missing or conflicting dependencies. (Re-run with `-Ylog-classpath` to see the problematic classpath.)
[error] A full rebuild may help if 'Actor.class' was compiled against an incompatible version of scala.
[error] C:\PROJECTS\active\Helios\src\main\scala\com\echostar\ese\helios\workers\NSPSG.scala:9: illegal inheritance;
[error]  self-type com.echostar.ese.helios.workers.NSPSG does not conform to akka.actor.Actor's selftype akka.actor.Actor
[error] class NSPSG extends Actor {
[error]                     ^
[error] three errors found
[error] (compile:compileIncremental) Compilation failed
[error] Total time: 3 s, completed Apr 4, 2016 9:19:45 AM

我的主要应用程序现在只是一个 println。它甚至不叫这个演员。

我是否在 scala 2.11 中使用了错误版本的 akka？ -Ylog-classpath 没有帮助

Answer 1

不知道是什么修复了它，但这里列出了我所做的事情并且项目现在可以编译。

1. 将 akka 依赖行更改为此（添加了双百分比并将版本更改回 2.4）

   libraryDependencies ++= Seq(
     "com.typesafe.akka" %% "akka-actor" % "2.4.0"
   )
   

2. 删除了我的运行配置并重新添加。 （我认为 main 的路径显示为红色（无效），因此重做它有助于解决它。我更改了我的包名称，但我认为 intelliJ 在 build-conf 中没有很好地选择重命名）

3. 从 IntelliJ 菜单（Scala 中的 Akka Main）启动了另一个测试项目，下载所有依赖项需要一些时间。所以也许我的项目需要这些并且没有下载它们？

4. 删除了注释掉的行（去掉了分号）。我认为这除了完全公开之外没有任何作用，从技术上讲，即使我的演员定义完全相同，我也确实接触了代码。