java.lang.ClassNotFoundException: play.core.server.NettyServer当更多的播放库被添加到build.sbt中时

Question

我对Scala，SBT和Play都是新手，所以请把它当作一个NooB查询。我正在为一个竞赛构建一个示例播放应用程序，并以反应性股票应用程序作为模板开始。为了扩展其功能，我需要添加安全性、JDBC连接等。

这是模板中提供的原始build.sbt文件-

scalaVersion := "2.11.1"

libraryDependencies ++= Seq(
  ws, // Play's web services module
  "com.typesafe.akka" %% "akka-actor" % "2.3.4",
  "com.typesafe.akka" %% "akka-slf4j" % "2.3.4",
  "org.webjars" % "bootstrap" % "2.3.1",
  "org.webjars" % "flot" % "0.8.0",
  "com.typesafe.akka" %% "akka-testkit" % "2.3.4" % "test"
)

在此基础上，我将"com.typesafe.play“% "anorm_2.11”% "2.4.0-M1“添加到列表中，在slf4j依赖项之后，应用程序能够编译和运行。

现在，如果我添加"com.typesafe.play“%”过滤器-helpers_2.11“% "2.4.0-M1”或"com.typesafe.play“% " play -jdbc_2.11”% "2.4.0-M1"，则play应用程序无法在Activator中编译带有消息"(echo:run) java.lang.ClassNotFoundException: play.core.server.NettyServer“。

Netty类肯定在类路径中。那又有什么问题呢？

我使用的是JDK 8。

scalaVersion := "2.11.1"

libraryDependencies ++= Seq(
  ws, // Play's web services module
  "com.typesafe.akka" %% "akka-actor" % "2.3.4",
  "com.typesafe.akka" %% "akka-slf4j" % "2.3.4",
  "org.webjars" % "bootstrap" % "2.3.1",
  "org.webjars" % "flot" % "0.8.0",
  "com.typesafe.akka" %% "akka-testkit" % "2.3.4" % "test",
  "com.typesafe.play" % "anorm_2.11" % "2.4.0-M1",
  "com.typesafe.play" % "filters-helpers_2.11" % "2.4.0-M1",
  "com.typesafe.play" % "play-jdbc_2.11" % "2.4.0-M1"
)

用原木

Reapplying settings...
Set current project to reactive-stocks (in build file:/D:/Miura/reactive-stocks/)
Reapplying settings...
Set current project to reactive-stocks (in build file:/D:/Miura/reactive-stocks/)
Reapplying settings...
Set current project to reactive-stocks (in build file:/D:/Miura/reactive-stocks/)
Reapplying settings...
Set current project to reactive-stocks (in build file:/D:/Miura/reactive-stocks/)
Running task... Cancel: sbt.TaskCancellationStrategy$Null$@571cf19b, check cycles: false
play.core.server.NettyServer
(echo:run) java.lang.ClassNotFoundException: play.core.server.NettyServer
Run complete.

Answer 1

正如在谷歌集团上回答的那样，问题在于混淆了Play库版本。股票模板为Play 2.3.3，但我试图添加的库为2.4。

此配置在build.sbt中工作

    libraryDependencies ++= Seq(
     jdbc,
     anorm,
     cache,
     ws

Answer 2

我也犯了这个错误：

 Exception in thread "main" java.lang.NoClassDefFoundError: play/core/server/NettyServer
 Caused by: java.lang.ClassNotFoundException: play.core.server.NettyServer
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:276)
at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)

但我的问题更愚蠢:许可。检查正在执行应用程序的用户是否具有正确的权限。

只是为了记录，所以其他人可以节省时间。