# AntlrTask don't working **URL:** \ **Category:** Help/Discuss\ **Tags:** plugins\ **Created:** [January 19, 2017, 3:32pm UTC](https://discuss.gradle.org/t/antlrtask-dont-working/21231 "2017-01-19T15:32:24Z")\ **Posts on this page:** 1\ **Page:** 1
**Author:** ![erlinve](https://avatars.discourse-cdn.com/v4/letter/e/b782af/32.png) [@erlinve](https://discuss.gradle.org/u/erlinve)\ **Post date:** [January 19, 2017, 3:32pm UTC](https://discuss.gradle.org/t/antlrtask-dont-working/21231/1 "2017-01-19T15:32:24Z")
I want to create some different tasks with type AntlrTask Default task (GenerateGrammarSource) - woking, But extending tasks fall with error, or can’t get any source files. Code: apply plugin: ‘java’ apply plugin: ‘antlr’ sourceCompatibility = 1.7 dependencies { ``` antlr ':antlr:4.5.3-complete' ``` } task genGramma(type: AntlrTask){ ``` source = fileTree("$rootDir/proj/bla-bla/gramma").include('**/*.g4') outputDirectory = file("$rootDir/proj/bla-bla/build/gen") ``` } ALL PATH ARE GOOD GRADLE 2.8 ERROR OUTPUT: FAILURE: Build failed with an exception. - What went wrong: Execution failed for task ‘:sql:genGramma’. > 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 ‘:sql:genGramma’. at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:69) at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:46) at org.gradle.api.internal.tasks.execution.PostExecutionAnalysisTaskExecuter.execute(PostExecutionAnalysisTaskExecuter.java:35) at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:64) at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:58) at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:52) at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:52) at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:53) at org.gradle.api.internal.tasks.execution.ExecuteAtMostOnceTaskExecuter.execute(ExecuteAtMostOnceTaskExecuter.java:43) at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:203) at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter$EventFiringTaskWorker.execute(DefaultTaskGraphExecuter.java:185) at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:62) at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:50) at org.gradle.execution.taskgraph.DefaultTaskPlanExecutor.process(DefaultTaskPlanExecutor.java:25) at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:110) 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$4.run(DefaultGradleLauncher.java:154) at org.gradle.internal.Factories$1.create(Factories.java:22) at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90) at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:52) at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:151) at org.gradle.initialization.DefaultGradleLauncher.access$200(DefaultGradleLauncher.java:32) at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:99) at org.gradle.initialization.DefaultGradleLauncher$1.create(DefaultGradleLauncher.java:93) at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:90) at org.gradle.internal.progress.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:62) at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:93) at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:82) at org.gradle.launcher.exec.InProcessBuildActionExecuter$DefaultBuildController.run(InProcessBuildActionExecuter.java:94) 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:43) at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:28) at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:77) at org.gradle.launcher.exec.ContinuousBuildActionExecuter.execute(ContinuousBuildActionExecuter.java:47) at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSuggestingBuildActionExecuter.java:51) at org.gradle.launcher.exec.DaemonUsageSuggestingBuildActionExecuter.execute(DaemonUsageSuggestingBuildActionExecuter.java:28) at org.gradle.launcher.cli.RunBuildAction.run(RunBuildAction.java:43) at org.gradle.internal.Actions$RunnableActionAdapter.execute(Actions.java:170) at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:237) at org.gradle.launcher.cli.CommandLineActionFactory$ParseAndBuildAction.execute(CommandLineActionFactory.java:210) at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:35) at org.gradle.launcher.cli.JavaRuntimeValidationAction.execute(JavaRuntimeValidationAction.java:24) at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:206) at org.gradle.launcher.cli.CommandLineActionFactory$WithLogging.execute(CommandLineActionFactory.java:169) at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:33) at org.gradle.launcher.cli.ExceptionReportingAction.execute(ExceptionReportingAction.java:22) at org.gradle.launcher.Main.doAction(Main.java:33) at org.gradle.launcher.bootstrap.EntryPoint.run(EntryPoint.java:45) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.gradle.launcher.bootstrap.ProcessBootstrap.runNoExit(ProcessBootstrap.java:54) at org.gradle.launcher.bootstrap.ProcessBootstrap.run(ProcessBootstrap.java:35) at org.gradle.launcher.GradleMain.main(GradleMain.java:23) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.gradle.wrapper.BootstrapMainStarter.start(BootstrapMainStarter.java:30) at org.gradle.wrapper.WrapperExecutor.execute(WrapperExecutor.java:129) at org.gradle.wrapper.GradleWrapperMain.main(GradleWrapperMain.java:61) Caused by: java.lang.NullPointerException at org.gradle.api.plugins.antlr.internal.AntlrSpecFactory.create(AntlrSpecFactory.java:45) at org.gradle.api.plugins.antlr.AntlrTask.execute(AntlrTask.java:203) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) at java.lang.reflect.Method.invoke(Unknown Source) at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:75) at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$IncrementalTaskAction.doExecute(AnnotationProcessingTaskFactory.java:244) at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.execute(AnnotationProcessingTaskFactory.java:220) at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$IncrementalTaskAction.execute(AnnotationProcessingTaskFactory.java:231) at org.gradle.api.internal.project.taskfactory.AnnotationProcessingTaskFactory$StandardTaskAction.execute(AnnotationProcessingTaskFactory.java:209) at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:80) at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:61)