Gradle Unable to blame file

:sonarqube FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':sonarqube'.
> Unable to blame file src/main/java/xxxxxtMapper.java

* Try:
Run with --info or --debug option to get more log output.

* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':sonarqube'.
	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$TaskExecutorWorker.processTask(AbstractTaskPlanExecutor.java:66)
	at org.gradle.execution.taskgraph.AbstractTaskPlanExecutor$TaskExecutorWorker.run(AbstractTaskPlanExecutor.java:50)
	at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:54)
	at org.gradle.internal.concurrent.StoppableExecutorImpl$1.run(StoppableExecutorImpl.java:40)
Caused by: java.lang.IllegalStateException: Unable to blame file src/main/java/xxxxxtMapper.java
	at org.sonar.plugins.scm.git.JGitBlameCommand.blame(JGitBlameCommand.java:128)
	at org.sonar.plugins.scm.git.JGitBlameCommand.access$000(JGitBlameCommand.java:45)
	at org.sonar.plugins.scm.git.JGitBlameCommand$1.call(JGitBlameCommand.java:113)
	at org.sonar.plugins.scm.git.JGitBlameCommand$1.call(JGitBlameCommand.java:110)
Caused by: java.lang.NullPointerException
	at org.eclipse.jgit.internal.storage.file.UnpackedObjectCache$Table.index(UnpackedObjectCache.java:146)
	at org.eclipse.jgit.internal.storage.file.UnpackedObjectCache$Table.contains(UnpackedObjectCache.java:109)
	at org.eclipse.jgit.internal.storage.file.UnpackedObjectCache.isUnpacked(UnpackedObjectCache.java:64)
	at org.eclipse.jgit.internal.storage.file.ObjectDirectory.openObject(ObjectDirectory.java:370)
	at org.eclipse.jgit.internal.storage.file.WindowCursor.open(WindowCursor.java:145)
	at org.eclipse.jgit.lib.ObjectReader.open(ObjectReader.java:229)
	at org.eclipse.jgit.blame.BlameGenerator.push(BlameGenerator.java:318)
	at org.eclipse.jgit.api.BlameCommand.call(BlameCommand.java:217)
	at org.sonar.plugins.scm.git.JGitBlameCommand.blame(JGitBlameCommand.java:123)
	... 3 more