为什么我的 build.sbt 正在寻找 2.11 版的 hadoop-streaming？

Question

我正在做关于 Apache Spark 的复数课程，有一次他们要求我们设置对 Hadoop-streaming 的依赖。我已将其添加到我的 build.sbt 文件中，但得到的结果出乎意料：

构建.sbt

name := "SparkPlayground"

version := "1.0"

scalaVersion := "2.11.8"

libraryDependencies += "org.apache.spark" %% "spark-core" % "2.0.0" % "provided"
libraryDependencies += "com.github.scala-incubator.io" %% "scala-io-core" % "0.4.3"
libraryDependencies += "com.github.scala-incubator.io" %% "scala-io-file" % "0.4.3"
libraryDependencies += "org.apache.hadoop" %% "hadoop-streaming" % "2.7.0"

错误信息

SBT 'SparkPlayground' project refresh failed
    Error:Error:Error while importing SBT project:<br/>...<br/><pre>[info] Resolving org.scala-sbt#task-system;0.13.8 ...

[info] Resolving org.scala-sbt#tasks;0.13.8 ...

[info] Resolving org.scala-sbt#tracking;0.13.8 ...

[info] Resolving org.scala-sbt#cache;0.13.8 ...

[info] Resolving org.scala-sbt#testing;0.13.8 ...

[info] Resolving org.scala-sbt#test-agent;0.13.8 ...

[info] Resolving org.scala-sbt#test-interface;1.0 ...

[info] Resolving org.scala-sbt#main-settings;0.13.8 ...

[info] Resolving org.scala-sbt#apply-macro;0.13.8 ...

[info] Resolving org.scala-sbt#command;0.13.8 ...

[info] Resolving org.scala-sbt#logic;0.13.8 ...

[info] Resolving org.scala-sbt#precompiled-2_8_2;0.13.8 ...

[info] Resolving org.scala-sbt#precompiled-2_9_2;0.13.8 ...

[info] Resolving org.scala-sbt#precompiled-2_9_3;0.13.8 ...

[trace] Stack trace suppressed: run 'last *:update' for the full output.

[trace] Stack trace suppressed: run 'last *:ssExtractDependencies' for the full output.

[error] (*:update) sbt.ResolveException: unresolved dependency: org.apache.hadoop#hadoop-streaming_2.11;2.6.0: not found

[error] (*:ssExtractDependencies) sbt.ResolveException: unresolved dependency: org.apache.hadoop#hadoop-streaming_2.11;2.6.0: not found

[error] Total time: 13 s, completed Sep 5, 2016 2:05:47 AM

从错误消息看来，sbt 出于某种原因正在寻找 hadoop-streaming_2.11，但我不知道这个 2.11 来自哪里。我对 Scala 和 sbt 还很陌生，所以我猜我在某处犯了一些愚蠢的错字

Answer 1

“如果你使用 groupID %% artifactID % revision 而不是 groupID % artifactID % revision （区别是 groupID 后面的双 %%），sbt 会将你项目的 Scala 版本添加到工件名称中。”

来自SBT manual。

所以你应该在这里使用 %。