我似乎无法正确编译一个简单的Scala项目。该目录如下所示：
.
├── build.gradle
└── src
└── Main.scala
build.gradle只是：
apply plugin: 'scala'
sourceSets {
main {
scala {
srcDir 'src'
}
}
}
它失败了这个迷人的小错误：
* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':compileScala'.
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:68)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:46)
at org.gradle.api.internal.tasks.execution.PostExecutionAnalysisTaskExecuter.execute(PostExecutionAnalysisTaskExecuter.java:34)
at org.gradle.api.internal.changedetection.CacheLockHandlingTaskExecuter$1.run(CacheLockHandlingTaskExecuter.java:34)
at org.gradle.internal.Factories$1.create(Factories.java:22)
at org.gradle.cache.internal.DefaultCacheAccess.longRunningOperation(DefaultCacheAccess.java:179)
at org.gradle.cache.internal.DefaultCacheAccess.longRunningOperation(DefaultCacheAccess.java:232)
at org.gradle.cache.internal.DefaultPersistentDirectoryStore.longRunningOperation(DefaultPersistentDirectoryStore.java:138)
at org.gradle.api.internal.changedetection.DefaultTaskArtifactStateCacheAccess.longRunningOperation(DefaultTaskArtifactStateCacheAccess.java:83)
at org.gradle.api.internal.changedetection.CacheLockHandlingTaskExecuter.execute(CacheLockHandlingTaskExecuter.java:32)
at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:55)
at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:57)
at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:41)
at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:51)
at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:52)
at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:42)
at org.gradle.api.internal.AbstractTask.executeWithoutThrowingTaskFailure(AbstractTask.java:247)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.executeTask(DefaultTaskPlanExecutor.java:52)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.processTask(DefaultTaskPlanExecutor.java:38)
at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java:30)
at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:83)
at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:29)
at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:61)
at org.gradle.execution.DefaultBuildExecuter.access$200(DefaultBuildExecuter.java:23)
at org.gradle.execution.DefaultBuildExecuter$2.proceed(DefaultBuildExecuter.java:67)
at org.gradle.api.internal.changedetection.TaskCacheLockHandlingBuildExecuter$1.run(TaskCacheLockHandlingBuildExecuter.java:31)
at org.gradle.internal.Factories$1.create(Factories.java:22)
at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:124)
at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:112)
at org.gradle.cache.internal.DefaultPersistentDirectoryStore.useCache(DefaultPersistentDirectoryStore.java:130)
at org.gradle.api.internal.changedetection.DefaultTaskArtifactStateCacheAccess.useCache(DefaultTaskArtifactStateCacheAccess.java:79)
at org.gradle.api.internal.changedetection.TaskCacheLockHandlingBuildExecuter.execute(TaskCacheLockHandlingBuildExecuter.java:29)
at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:61)
at org.gradle.execution.DefaultBuildExecuter.access$200(DefaultBuildExecuter.java:23)
at org.gradle.execution.DefaultBuildExecuter$2.proceed(DefaultBuildExecuter.java:67)
at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:61)
at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:54)
at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:158)
at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:113)
at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:81)
at org.gradle.launcher.cli.ExecuteBuildAction.run(ExecuteBuildAction.java:38)
at org.gradle.launcher.exec.InProcessGradleLauncherActionExecuter.execute(InProcessGradleLauncherActionExecuter.java:39)
at org.gradle.launcher.exec.InProcessGradleLauncherActionExecuter.execute(InProcessGradleLauncherActionExecuter.java:25)
at org.gradle.launcher.cli.RunBuildAction.run(RunBuildAction.java:50)
at org.gradle.api.internal.Actions$RunnableActionAdapter.execute(Actions.java:137)
at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:201)
at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:174)
at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:170)
at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:139)
at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:33)
at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:22)
at org.gradle.launcher.Main.doAction(Main.java:48)
at org.gradle.launcher.bootstrap.EntryPoint.run(EntryPoint.java:45)
at org.gradle.launcher.Main.main(Main.java:39)
at org.gradle.launcher.bootstrap.ProcessBootstrap.runNoExit(ProcessBootstrap.java:50)
at org.gradle.launcher.bootstrap.ProcessBootstrap.run(ProcessBootstrap.java:32)
at org.gradle.launcher.GradleMain.main(GradleMain.java:26)
Caused by: java.lang.NullPointerException: Cannot invoke method withInputStream() on null object
at org.gradle.api.internal.project.AntBuilderDelegate.taskdef(DefaultIsolatedAntBuilder.groovy:136)
at org.gradle.api.internal.tasks.scala.AntScalaCompiler$_execute_closure1.doCall(AntScalaCompiler.groovy:62)
at org.gradle.api.internal.ClosureBackedAction.execute(ClosureBackedAction.java:58)
at org.gradle.util.ConfigureUtil.configure(ConfigureUtil.java:130)
at org.gradle.util.ConfigureUtil.configure(ConfigureUtil.java:91)
at org.gradle.util.ConfigureUtil$configure.call(Unknown Source)
at org.gradle.api.internal.project.DefaultIsolatedAntBuilder.execute(DefaultIsolatedAntBuilder.groovy:112)
at org.gradle.api.internal.project.IsolatedAntBuilder$execute.call(Unknown Source)
at org.gradle.api.internal.tasks.scala.AntScalaCompiler.execute(AntScalaCompiler.groovy:61)
at org.gradle.api.internal.tasks.scala.AntScalaCompiler.execute(AntScalaCompiler.groovy)
at org.gradle.api.internal.tasks.scala.DefaultScalaJavaJointCompiler.execute(DefaultScalaJavaJointCompiler.java:35)
at org.gradle.api.internal.tasks.scala.DefaultScalaJavaJointCompiler.execute(DefaultScalaJavaJointCompiler.java:25)
at org.gradle.api.internal.tasks.scala.DelegatingScalaCompiler.execute(DelegatingScalaCompiler.java:31)
at org.gradle.api.internal.tasks.scala.DelegatingScalaCompiler.execute(DelegatingScalaCompiler.java:22)
at org.gradle.api.internal.tasks.compile.IncrementalJavaCompilerSupport.execute(IncrementalJavaCompilerSupport.java:33)
at org.gradle.api.internal.tasks.compile.IncrementalJavaCompilerSupport.execute(IncrementalJavaCompilerSupport.java:23)
at org.gradle.api.tasks.scala.ScalaCompile.compile(ScalaCompile.java:131)
at org.gradle.api.internal.BeanDynamicObject$MetaClassAdapter.invokeMethod(BeanDynamicObject.java:216)
at org.gradle.api.internal.BeanDynamicObject.invokeMethod(BeanDynamicObject.java:122)
at org.gradle.api.internal.CompositeDynamicObject.invokeMethod(CompositeDynamicObject.java:147)
at org.gradle.api.tasks.scala.ScalaCompile_Decorated.invokeMethod(Unknown Source)
at org.gradle.util.ReflectionUtil.invoke(ReflectionUtil.groovy:23)
at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$4.execute(AnnotationProcessingTaskFactory.java:161)
at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$4.execute(AnnotationProcessingTaskFactory.java:156)
at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:472)
at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:461)
at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:60)
... 57 more
BUILD FAILED
我的gradle --version是：
------------------------------------------------------------
Gradle 1.3
------------------------------------------------------------
Gradle build time: Tuesday, November 20, 2012 11:37:38 AM UTC
Groovy: 1.8.6
Ant: Apache Ant(TM) version 1.8.4 compiled on May 22 2012
Ivy: 2.2.0
JVM: 1.6.0_24 (Sun Microsystems Inc. 20.0-b12)
OS: Linux 3.2.0-29-generic amd64
世界上出了什么问题？
答案 0 :(得分：5)
您尚未声明要使用哪个Scala版本，如文档和示例所示。 （错误消息在即将发布的Gradle 1.4中得到修复。）
repositories {
mavenCentral()
}
dependencies {
scalaTools "org.scala-lang:scala-compiler:2.9.2"
compile "org.scala-lang:scala-library:2.9.2"
}
答案 1 :(得分：0)
我在Gradle 2.1上遇到了这个问题。 （虽然我没有得到同样的错误，谷歌发现了这个。）我有一个“由于：由于内部编译器错误导致编译失败;有关详细信息，请参阅错误输出。”错误，没有告诉我任何事情。
我没有看到anything on the documentation表示我需要使用scalaTools或类似的东西。
我最终关闭了基于ant的编译，而不是使用TypeSafe Zinc编译器
tasks.withType(ScalaCompile) {
scalaCompileOptions.useAnt = false
}