scala - Gradle Scala 2.12

Question

使用Gradle和 bundle 的scala 2.12甚至原因java.lang.ClassNotFoundException: scala.Product$class都无法编译最简单的scala代码。使用scala 2.11.8进行项目构建。异常(exception)如下:

org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':compileScala'.
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:84)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:55)
        at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:62)
        at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58)
        at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:88)
        at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:46)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:51)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
        at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43)
        at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:34)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.execute(DefaultTaskGraphExecuter.java:236)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker$1.execute(DefaultTaskGraphExecuter.java:228)
        at org.gradle.internal.Transformers$4.transform(Transformers.java:169)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:106)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:61)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:228)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:215)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:77)
        at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:58)
        at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java:32)
        at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:113)
        at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:37)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
        at org.gradle.execution.DefaultBuildExecuter.access$000(DefaultBuildExecuter.java:23)
        at org.gradle.execution.DefaultBuildExecuter$1.proceed(DefaultBuildExecuter.java:43)
        at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:37)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:30)
        at org.gradle.initialization.DefaultGradleLauncher$3.execute(DefaultGradleLauncher.java:196)
        at org.gradle.initialization.DefaultGradleLauncher$3.execute(DefaultGradleLauncher.java:193)
        at org.gradle.internal.Transformers$4.transform(Transformers.java:169)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:106)
        at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:56)
        at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:193)
        at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:119)
        at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:102)
        at org.gradle.launcher.exec.GradleBuildController.run(GradleBuildController.java:71)
        at org.gradle.tooling.internal.provider.ExecuteBuildActionRunner.run(ExecuteBuildActionRunner.java:28)
        at org.gradle.launcher.exec.ChainingBuildActionRunner.run(ChainingBuildActionRunner.java:35)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:41)
        at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:26)
        at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:75)
        at org.gradle.tooling.internal.provider.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:49)
        at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:44)
        at org.gradle.tooling.internal.provider.ServicesSetupBuildActionExecuter.execute(ServicesSetupBuildActionExecuter.java:29)
        at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:67)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:47)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:26)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.RequestStopIfSingleUsedDaemon.execute(RequestStopIfSingleUsedDaemon.java:34)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:74)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:72)
        at org.gradle.util.Swapper.swap(Swapper.java:38)
        at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:72)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.LogAndCheckHealth.execute(LogAndCheckHealth.java:55)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:60)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:72)
        at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:36)
        at org.gradle.launcher.daemon.server.api.DaemonCommandExecution.proceed(DaemonCommandExecution.java:120)
        at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:50)
        at org.gradle.launcher.daemon.server.DaemonStateCoordinator$1.run(DaemonStateCoordinator.java:297)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:54)
        at org.gradle.internal.concurrent.StoppableExecutorImpl$1.run(StoppableExecutorImpl.java:40)
Caused by: java.lang.NoClassDefFoundError: scala/Product$class
        at com.typesafe.zinc.JarFile.<init>(Setup.scala:28)
        at com.typesafe.zinc.Setup$.<init>(Setup.scala:52)
        at com.typesafe.zinc.Setup$.<clinit>(Setup.scala)
        at com.typesafe.zinc.Setup.zincVersion(Setup.scala)
        at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory.createParallelSafeCompiler(ZincScalaCompilerFactory.java:58)
        at org.gradle.api.internal.tasks.scala.ZincScalaCompiler$Compiler.execute(ZincScalaCompiler.java:60)
        at org.gradle.api.internal.tasks.scala.ZincScalaCompiler.execute(ZincScalaCompiler.java:49)
        at org.gradle.api.internal.tasks.scala.ZincScalaCompiler.execute(ZincScalaCompiler.java:35)
        at org.gradle.api.internal.tasks.compile.daemon.AbstractDaemonCompiler$CompilerWorkerAdapter.execute(AbstractDaemonCompiler.java:73)
        at org.gradle.api.internal.tasks.compile.daemon.AbstractDaemonCompiler$CompilerWorkerAdapter.execute(AbstractDaemonCompiler.java:64)
        at org.gradle.process.internal.daemon.WorkerDaemonServer.execute(WorkerDaemonServer.java:28)
        at org.gradle.api.internal.tasks.compile.daemon.AbstractDaemonCompiler$CompilerDaemonServer.execute(AbstractDaemonCompiler.java:91)
        at org.gradle.process.internal.worker.request.WorkerAction.run(WorkerAction.java:87)
        at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
        at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
        at org.gradle.internal.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:377)
        ... 2 more
Caused by: java.lang.ClassNotFoundException: scala.Product$class
        ... 18 more

简单的类:

object Main extends App {
    println("123")
}

build.gradle文件失败。将属性更改为 ext.scala_version = "2.11.8"可使一切正常。

apply plugin: 'scala'

ext.scala_version = "2.12.1"

configurations.all {
    resolutionStrategy.force "org.scala-lang:scala-library:$scala_version"
}

repositories {
    mavenCentral()
}

dependencies {
    compile "org.scala-lang:scala-library:$scala_version"
}

task wrapper(type: Wrapper) {
    gradleVersion = '3.3'
}

我还将versin 3.3的gradle包装器与以下 gradle-wrapper.properties一起使用:

distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
distributionUrl=https\://services.gradle.org/distributions/gradle-3.3-bin.zip

有人可以帮忙吗？也许这是一个众所周知的问题，但我还没有找到解决方案。

Answer 1

我知道这是一个非常老的问题，但是如果有人偶然发现java.lang.ClassNotFoundException: scala.Product$class这个问题，对我来说问题是我正在引用使用Scala 2.11编译的类

将我所有的内部(仍在使用Scala 2.11的其他项目)和外部依赖项(包括Scala库，例如Akka)更改为兼容的Scala 2.12版本，可以解决此问题。