NPE trying to safely delete a local variable

java.lang.NullPointerExceptionjava.lang.NullPointerException at org.netbeans.modules.refactoring.java.plugins.SafeDeleteRefactoringPlugin$5.run(SafeDeleteRefactoringPlugin.java:390) at org.netbeans.modules.refactoring.java.plugins.SafeDeleteRefactoringPlugin$5.run(SafeDeleteRefactoringPlugin.java:383) at org.netbeans.api.java.source.JavaSource$MultiTask.run(JavaSource.java:502) at org.netbeans.modules.parsing.impl.TaskProcessor.callUserTask(TaskProcessor.java:586) at org.netbeans.modules.parsing.api.ParserManager$UserTaskAction.run(ParserManager.java:130) at org.netbeans.modules.parsing.api.ParserManager$UserTaskAction.run(ParserManager.java:114) at org.netbeans.modules.parsing.impl.TaskProcessor$2.call(TaskProcessor.java:181) at org.netbeans.modules.parsing.impl.TaskProcessor$2.call(TaskProcessor.java:178) at org.netbeans.modules.masterfs.filebasedfs.utils.FileChangedManager.priorityIO(FileChangedManager.java:153) at org.netbeans.modules.masterfs.providers.ProvidedExtensions.priorityIO(ProvidedExtensions.java:335) at org.netbeans.modules.parsing.nb.DataObjectEnvFactory.runPriorityIO(DataObjectEnvFactory.java:118) at org.netbeans.modules.parsing.impl.Utilities.runPriorityIO(Utilities.java:67) at org.netbeans.modules.parsing.impl.TaskProcessor.runUserTask(TaskProcessor.java:178) at org.netbeans.modules.parsing.api.ParserManager.parse(ParserManager.java:81) at org.netbeans.api.java.source.JavaSource.runUserActionTaskImpl(JavaSource.java:452) at org.netbeans.api.java.source.JavaSource.runUserActionTask(JavaSource.java:423) at org.netbeans.modules.refactoring.java.plugins.SafeDeleteRefactoringPlugin.getWhereUsedItemNames(SafeDeleteRefactoringPlugin.java:383) at org.netbeans.modules.refactoring.java.plugins.SafeDeleteRefactoringPlugin.prepare(SafeDeleteRefactoringPlugin.java:272)[catch] at org.netbeans.modules.refactoring.api.AbstractRefactoring.pluginsPrepare2(AbstractRefactoring.java:417) at org.netbeans.modules.refactoring.api.AbstractRefactoring.pluginsPrepare(AbstractRefactoring.java:401) at org.netbeans.modules.refactoring.api.AbstractRefactoring.prepare(AbstractRefactoring.java:212) at org.netbeans.modules.refactoring.spi.impl.ParametersPanel$Prepare.run(ParametersPanel.java:1063) at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1418) at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:45) at org.openide.util.lookup.Lookups.executeWith(Lookups.java:278) at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2033)