java.lang.NullPointerException
   at org.netbeans.modules.profiler.heapwalk.OverviewController.printInstance(OverviewController.java:589)
   at org.netbeans.modules.profiler.heapwalk.OverviewController.getStackTrace(OverviewController.java:520)
   at org.netbeans.modules.profiler.heapwalk.OverviewController.computeThreads(OverviewController.java:324)
   at org.netbeans.modules.profiler.heapwalk.ui.OverviewControllerUI$1.run(OverviewControllerUI.java:142)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1424)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1968)