Compilation failing with NPE


(David Resnick) #1

I’m getting a NullPointerException when attempting to build a project. The problem is environment related; the same project builds successfully on other Windows and Linux machines.

gradlew --version
  ------------------------------------------------------------
Gradle 1.0-milestone-9
------------------------------------------------------------
  Gradle build time: Tuesday, March 13, 2012 4:10:09 PM UTC
Groovy: 1.8.6
Ant: Apache Ant(TM) version 1.8.2 compiled on December 20 2010
Ivy: 2.2.0
JVM: 1.7.0_04 (Oracle Corporation 23.0-b21)
OS: Windows 7 6.1 amd64

:proj:compileJava
  FAILURE: Build failed with an exception.
  * What went wrong:
Execution failed for task ':proj:compileJava'.
> java.lang.NullPointerException (no error message)
  * Try:
Run with --info or --debug option to get more log output.
  * Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':proj:compileJava'.
        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.cache.internal.DefaultCacheAccess$2.create(DefaultCacheAccess.java:200)
        at org.gradle.cache.internal.DefaultCacheAccess.longRunningOperation(DefaultCacheAccess.java:172)
        at org.gradle.cache.internal.DefaultCacheAccess.longRunningOperation(DefaultCacheAccess.java:198)
        at org.gradle.cache.internal.DefaultPersistentDirectoryStore.longRunningOperation(DefaultPersistentDirectoryStore.java:111)
        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.DefaultTaskGraphExecuter.executeTask(DefaultTaskGraphExecuter.java:192)
        at org.gradle.execution.DefaultTaskGraphExecuter.doExecute(DefaultTaskGraphExecuter.java:177)
        at org.gradle.execution.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:83)
        at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:36)
        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.cache.internal.DefaultCacheAccess$1.create(DefaultCacheAccess.java:111)
        at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:126)
        at org.gradle.cache.internal.DefaultCacheAccess.useCache(DefaultCacheAccess.java:109)
        at org.gradle.cache.internal.DefaultPersistentDirectoryStore.useCache(DefaultPersistentDirectoryStore.java:103)
        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$2.proceed(DefaultBuildExecuter.java:67)
        at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:61)
        at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:54)
        at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:155)
        at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:110)
        at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:78)
        at org.gradle.launcher.cli.RunBuildAction.execute(RunBuildAction.java:42)
        at org.gradle.launcher.cli.RunBuildAction.execute(RunBuildAction.java:28)
        at org.gradle.launcher.exec.ExceptionReportingAction.execute(ExceptionReportingAction.java:32)
        at org.gradle.launcher.exec.ExceptionReportingAction.execute(ExceptionReportingAction.java:21)
        at org.gradle.launcher.cli.CommandLineActionFactory$WithLoggingAction.execute(CommandLineActionFactory.java:302)
        at org.gradle.launcher.cli.CommandLineActionFactory$WithLoggingAction.execute(CommandLineActionFactory.java:286)
        at org.gradle.launcher.Main.doAction(Main.java:48)
        at org.gradle.launcher.exec.EntryPoint$1.execute(EntryPoint.java:53)
        at org.gradle.launcher.exec.EntryPoint$1.execute(EntryPoint.java:51)
        at org.gradle.launcher.exec.Execution.execute(Execution.java:28)
        at org.gradle.launcher.exec.EntryPoint.run(EntryPoint.java:39)
        at org.gradle.launcher.Main.main(Main.java:39)
        at org.gradle.launcher.ProcessBootstrap.runNoExit(ProcessBootstrap.java:51)
        at org.gradle.launcher.ProcessBootstrap.run(ProcessBootstrap.java:33)
        at org.gradle.launcher.GradleMain.main(GradleMain.java:24)
        at org.gradle.wrapper.BootstrapMainStarter.start(BootstrapMainStarter.java:33)
        at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:124)
        at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:53)
Caused by: java.lang.NullPointerException
        at org.gradle.api.internal.tasks.compile.jdk6.Jdk6JavaCompiler.createCompileTask(Jdk6JavaCompiler.java:52)
        at org.gradle.api.internal.tasks.compile.jdk6.Jdk6JavaCompiler.execute(Jdk6JavaCompiler.java:39)
        at org.gradle.api.internal.tasks.compile.jdk6.Jdk6JavaCompiler.execute(Jdk6JavaCompiler.java:33)
        at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.delegateAndHandleErrors(NormalizingJavaCompiler.java:95)
        at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:48)
        at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:34)
        at org.gradle.api.internal.tasks.compile.DelegatingJavaCompiler.execute(DelegatingJavaCompiler.java:29)
        at org.gradle.api.internal.tasks.compile.DelegatingJavaCompiler.execute(DelegatingJavaCompiler.java:20)
        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.compile.Compile.compile(Compile.java:60)
        at org.gradle.api.internal.BeanDynamicObject$MetaClassAdapter.invokeMethod(BeanDynamicObject.java:196)
        at org.gradle.api.internal.BeanDynamicObject.invokeMethod(BeanDynamicObject.java:102)
        at org.gradle.api.internal.CompositeDynamicObject.invokeMethod(CompositeDynamicObject.java:99)
        at org.gradle.api.tasks.compile.Compile_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:150)
        at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$4.execute(AnnotationProcessingTaskFactory.java:145)
        at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:477)
        at org.gradle.api.internal.AbstractTask$TaskActionWrapper.execute(AbstractTask.java:466)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:60)
        ... 57 more
    BUILD FAILED

(Peter Niederwieser) #2

This can happens when you run Gradle with a JRE (6) instead of a JDK. Recent versions of Gradle provide a better error message (“cannot find compiler…”). You should be able to fix this by pointing ‘JAVA_HOME’ to a JDK.


(David Resnick) #3

Thanks, that did the trick.