由于我是Samza和Scala的新手，因此不确定如何解决此问题。
我正在关注本教程，并且目前停留在此部分:https://github.com/apache/samza-hello-samza#2-start-a-grid
这是我收到的错误消息
> Task :samza-core_2.11:compileScala FAILED
error: scala.reflect.internal.MissingRequirementError: object java.lang.Object in compiler mirror not found.
at scala.reflect.internal.MissingRequirementError$.signal(MissingRequirementError.scala:17)
at scala.reflect.internal.MissingRequirementError$.notFound(MissingRequirementError.scala:18)
at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:53)
at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:45)
at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:45)
at scala.reflect.internal.Mirrors$RootsBase.getModuleOrClass(Mirrors.scala:66)
at scala.reflect.internal.Mirrors$RootsBase.getClassByName(Mirrors.scala:102)
at scala.reflect.internal.Mirrors$RootsBase.getRequiredClass(Mirrors.scala:105)
at scala.reflect.internal.Definitions$DefinitionsClass.ObjectClass$lzycompute(Definitions.scala:257)
at scala.reflect.internal.Definitions$DefinitionsClass.ObjectClass(Definitions.scala:257)
at scala.reflect.internal.Definitions$DefinitionsClass.init(Definitions.scala:1394)
at scala.tools.nsc.Global$Run.<init>(Global.scala:1215)
at scala.tools.nsc.Driver.doCompile(Driver.scala:31)
at scala.tools.nsc.MainClass.doCompile(Main.scala:23)
at scala.tools.nsc.Driver.process(Driver.scala:51)
at scala.tools.nsc.Main.process(Main.scala)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at sbt.compiler.RawCompiler.apply(RawCompiler.scala:33)
at sbt.compiler.AnalyzingCompiler$$anonfun$compileSources$1$$anonfun$apply$2.apply(AnalyzingCompiler.scala:159)
at sbt.compiler.AnalyzingCompiler$$anonfun$compileSources$1$$anonfun$apply$2.apply(AnalyzingCompiler.scala:155)
at sbt.IO$.withTemporaryDirectory(IO.scala:358)
at sbt.compiler.AnalyzingCompiler$$anonfun$compileSources$1.apply(AnalyzingCompiler.scala:155)
at sbt.compiler.AnalyzingCompiler$$anonfun$compileSources$1.apply(AnalyzingCompiler.scala:152)
at sbt.IO$.withTemporaryDirectory(IO.scala:358)
at sbt.compiler.AnalyzingCompiler$.compileSources(AnalyzingCompiler.scala:152)
at sbt.compiler.IC$.compileInterfaceJar(IncrementalCompiler.scala:58)
at sbt.compiler.IC.compileInterfaceJar(IncrementalCompiler.scala)
at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory.getCompilerInterface(ZincScalaCompilerFactory.java:119)
at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory.access$200(ZincScalaCompilerFactory.java:48)
at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory$2.apply(ZincScalaCompilerFactory.java:90)
at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory$2.apply(ZincScalaCompilerFactory.java:87)
at com.typesafe.zinc.Cache.get(Cache.scala:41)
at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory.createCompiler(ZincScalaCompilerFactory.java:87)
at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory.access$100(ZincScalaCompilerFactory.java:48)
at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory$1.create(ZincScalaCompilerFactory.java:76)
at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory$1.create(ZincScalaCompilerFactory.java:72)
at org.gradle.internal.SystemProperties.withSystemProperty(SystemProperties.java:141)
at org.gradle.api.internal.tasks.scala.ZincScalaCompilerFactory.createParallelSafeCompiler(ZincScalaCompilerFactory.java:72)
at org.gradle.api.internal.tasks.scala.ZincScalaCompiler$Compiler.execute(ZincScalaCompiler.java:64)
at org.gradle.api.internal.tasks.scala.ZincScalaCompiler.execute(ZincScalaCompiler.java:52)
at org.gradle.api.internal.tasks.scala.ZincScalaCompiler.execute(ZincScalaCompiler.java:38)
at org.gradle.api.internal.tasks.compile.daemon.AbstractDaemonCompiler$CompilerCallable.call(AbstractDaemonCompiler.java:88)
at org.gradle.api.internal.tasks.compile.daemon.AbstractDaemonCompiler$CompilerCallable.call(AbstractDaemonCompiler.java:76)
at org.gradle.workers.internal.DefaultWorkerServer.execute(DefaultWorkerServer.java:42)
at org.gradle.workers.internal.WorkerDaemonServer.execute(WorkerDaemonServer.java:46)
at org.gradle.workers.internal.WorkerDaemonServer.execute(WorkerDaemonServer.java:30)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at org.gradle.process.internal.worker.request.WorkerAction.run(WorkerAction.java:101)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
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.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:155)
at org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:137)
at org.gradle.internal.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:404)
at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1135)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
at java.base/java.lang.Thread.run(Thread.java:844)
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':samza-core_2.11:compileScala'.
> org.gradle.internal.serialize.PlaceholderException (no error message)
最佳答案
在网格文件中，将samza下载URL替换为https://github.com/apache/samza.git删除.m2文件夹，然后重新启动网格。它应该工作。