ConcurrentModficationException when running imported ant task from build file

I am getting a concurrent modification exception when trying to run a task from ant build file import in a multi module project with various sub projects .

The exception doesn’t say much other then this

  • What went wrong:
    java.util.ConcurrentModificationException (no error message)

    Exception

    • Try:
      Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output.

    BUILD FAILED

    Total time: 0.909 secs
    [sts] Build failed
    org.gradle.tooling.BuildException: Could not execute build using Gradle distribution ‘https://services.gradle.org/distributions/gradle-2.2.1-bin.zip’.
    at org.gradle.tooling.internal.consumer.ResultHandlerAdapter.onFailure(ResultHandlerAdapter.java:57)
    at org.gradle.tooling.internal.consumer.async.DefaultAsyncConsumerActionExecutor$1$1.run(DefaultAsyncConsumerActionExecutor.java:57)
    at org.gradle.internal.concurrent.DefaultExecutorFactory$StoppableExecutorImpl$1.run(DefaultExecutorFactory.java:64)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
    at org.gradle.tooling.internal.consumer.BlockingResultHandler.getResult(BlockingResultHandler.java:46)
    at org.gradle.tooling.internal.consumer.DefaultBuildLauncher.run(DefaultBuildLauncher.java:71)
    at org.springsource.ide.eclipse.gradle.core.TaskUtil.execute(TaskUtil.java:117)
    at org.springsource.ide.eclipse.gradle.core.launch.GradleProcess$1.doit(GradleProcess.java:92)
    at org.springsource.ide.eclipse.gradle.core.util.GradleRunnable$1.run(GradleRunnable.java:53)
    at org.eclipse.core.internal.jobs.Worker.run(Worker.java:55)
    Caused by: org.gradle.internal.exceptions.LocationAwareException
    at org.gradle.initialization.DefaultExceptionAnalyser.transform(DefaultExceptionAnalyser.java:77)
    at org.gradle.initialization.MultipleBuildFailuresExceptionAnalyser.transform(MultipleBuildFailuresExceptionAnalyser.java:47)
    at org.gradle.initialization.StackTraceSanitizingExceptionAnalyser.transform(StackTraceSanitizingExceptionAnalyser.java:30)
    at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:108)
    at org.gradle.initialization.DefaultGradleLauncher.run(DefaultGradleLauncher.java:86)
    at org.gradle.launcher.exec.InProcessBuildActionExecuter$DefaultBuildController.run(InProcessBuildActionExecuter.java:80)
    at org.gradle.tooling.internal.provider.BuildModelAction.run(BuildModelAction.java:43)
    at org.gradle.tooling.internal.provider.BuildModelAction.run(BuildModelAction.java:30)
    at org.gradle.tooling.internal.provider.ConfiguringBuildAction.run(ConfiguringBuildAction.java:119)
    at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:36)
    at org.gradle.launcher.exec.InProcessBuildActionExecuter.execute(InProcessBuildActionExecuter.java:26)
    at org.gradle.launcher.daemon.server.exec.ExecuteBuild.doBuild(ExecuteBuild.java:47)
    at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:34)
    at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:119)
    at org.gradle.launcher.daemon.server.exec.WatchForDisconnection.execute(WatchForDisconnection.java:35)
    at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:119)
    at org.gradle.launcher.daemon.server.exec.ResetDeprecationLogger.execute(ResetDeprecationLogger.java:24)
    at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:119)
    at org.gradle.launcher.daemon.server.exec.StartStopIfBuildAndStop.execute(StartStopIfBuildAndStop.java:33)
    at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:119)
    at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:71)
    at org.gradle.launcher.daemon.server.exec.ForwardClientInput$2.call(ForwardClientInput.java:69)
    at org.gradle.util.Swapper.swap(Swapper.java:38)
    at org.gradle.launcher.daemon.server.exec.ForwardClientInput.execute(ForwardClientInput.java:69)
    at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:119)
    at org.gradle.launcher.daemon.server.exec.LogToClient.doBuild(LogToClient.java:60)
    at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:34)
    at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:119)
    at org.gradle.launcher.daemon.server.exec.EstablishBuildEnvironment.doBuild(EstablishBuildEnvironment.java:70)
    at org.gradle.launcher.daemon.server.exec.BuildCommandOnly.execute(BuildCommandOnly.java:34)
    at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:119)
    at org.gradle.launcher.daemon.server.exec.DaemonHygieneAction.execute(DaemonHygieneAction.java:39)
    at org.gradle.launcher.daemon.server.exec.DaemonCommandExecution.proceed(DaemonCommandExecution.java:119)
    at org.gradle.launcher.daemon.server.exec.StartBuildOrRespondWithBusy$1.run(StartBuildOrRespondWithBusy.java:46)
    at org.gradle.launcher.daemon.server.DaemonStateCoordinator$1.run(DaemonStateCoordinator.java:246)
    at org.gradle.internal.concurrent.DefaultExecutorFactory$StoppableExecutorImpl$1.run(DefaultExecutorFactory.java:64)
    Caused by: java.util.ConcurrentModificationException
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.removeShouldRunAfterSuccessorsIfTheyImposeACycle(DefaultTaskExecutionPlan.java:326)
    at org.gradle.execution.taskgraph.DefaultTaskExecutionPlan.determineExecutionPlan(DefaultTaskExecutionPlan.java:244)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.ensurePopulated(DefaultTaskGraphExecuter.java:150)
    at org.gradle.execution.taskgraph.DefaultTaskGraphExecuter.execute(DefaultTaskGraphExecuter.java:84)
    at org.gradle.execution.SelectedTaskExecutionAction.execute(SelectedTaskExecutionAction.java:29)
    at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:62)
    at org.gradle.execution.DefaultBuildExecuter.access$200(DefaultBuildExecuter.java:23)
    at org.gradle.execution.DefaultBuildExecuter$2.proceed(DefaultBuildExecuter.java:68)
    at org.gradle.execution.DryRunBuildExecutionAction.execute(DryRunBuildExecutionAction.java:32)
    at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:62)
    at org.gradle.execution.DefaultBuildExecuter.execute(DefaultBuildExecuter.java:55)
    at org.gradle.initialization.DefaultGradleLauncher.doBuildStages(DefaultGradleLauncher.java:149)
    at org.gradle.initialization.DefaultGradleLauncher.doBuild(DefaultGradleLauncher.java:106)
    … 32 more
    [sts] Time taken: 0 min, 1 sec
    [sts] -----------------------------------------------------

      indent preformatted text by 4 spaces
    

I have same build.gradle file in other sub project but i am able to execute the tasks from gradle with out any issues

my gradle file for ant import

ant.importBuild('build.xml')
{
antTargetName -> 'a-' +antTargetName
} 

Please help me to resolve the issue. I am using gradle 2.5

Are you sure you are using Gradle 2.5? Line 326 of DefaultTaskExecutionPlan doesn’t correspond to removeShouldRunAfterSuccessorsIfTheyImposeACycle on master, nor on 2.5 : https://github.com/gradle/gradle/blob/e18bac0b6db96f139ec4a94d6e922978077a922c/subprojects/core/src/main/groovy/org/gradle/execution/taskgraph/DefaultTaskExecutionPlan.java#L326-326

Thanks for pointing it out. I have set my GRADLE_HOME to 2.5 but eclipse is not using it. I have set the wraper to use 2.5 and it works now. Thank you very much.