java.lang.NullPointerException
   at org.netbeans.modules.profiler.actions.CompareSnapshotsAction$SelectExternalSnapshotsPanel$4.doInBackground(CompareSnapshotsAction.java:339)
   at org.netbeans.lib.profiler.ui.SwingWorker$2.run(SwingWorker.java:159)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1432)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2042)