Migration Playframework迁移到2.3.9缺少play文档并阻止startDevMode

从playframework-2.2.4迁移到playframework-2.3.9后，运行时出现以下错误：

[namek] $ run

java.util.NoSuchElementException: head of empty list
        at scala.collection.immutable.Nil$.head(List.scala:337)
        at scala.collection.immutable.Nil$.head(List.scala:334)
        at play.runsupport.Reloader$.startDevMode(Reloader.scala:184)
        at play.PlayRun$$anonfun$playRunTask$1$$anonfun$apply$2$$anonfun$apply$3.devModeServer$lzycompute$1(PlayRun.scala:75)
        at play.PlayRun$$anonfun$playRunTask$1$$anonfun$apply$2$$anonfun$apply$3.play$PlayRun$class$$anonfun$$anonfun$$anonfun$$devModeServer$1(PlayRun.scala:75)
        at play.PlayRun$$anonfun$playRunTask$1$$anonfun$apply$2$$anonfun$apply$3.apply(PlayRun.scala:98)
        at play.PlayRun$$anonfun$playRunTask$1$$anonfun$apply$2$$anonfun$apply$3.apply(PlayRun.scala:54)
        at scala.Function1$$anonfun$compose$1.apply(Function1.scala:47)
[trace] Stack trace suppressed: run last compile:run for the full output.
[error] (compile:run) java.util.NoSuchElementException: head of empty list
[error] Total time: 3 s, completed 26-May-2015 12:35:03

在源文件Reloader.scala:184（）中，我看到以docsClasspath:Classpath的名称对“playdocs”的引用，该名称在startDevMode中作为参数接收

val docsJarFile = {
        val f = docsClasspath.filter(_.getName.startsWith("play-docs")).head
        new JarFile(f)
      }

我该怎么办？我找不到关于这个名字的任何参考资料

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更新 在旧版本中，playDocsJar似乎使用了headOption而不是head（）

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作为一种解决方法，我创建了一个DocsApplication并添加了一个虚拟库

libraryDependencies += "com.typesafe.play" %% "play-docs" % play.core.PlayVersion.current % "docs"

libraryDependencies += "com.typesafe.play" %% "play-docs" % play.core.PlayVersion.current % "docs"