java.lang.NullPointerException
        at org.netbeans.modules.profiler.heapwalk.model.ObjectNode$1.computeChildren(ObjectNode.java:167)
        at org.netbeans.modules.profiler.heapwalk.model.BrowserUtils$1$1.run(BrowserUtils.java:211)
        at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:602)
        at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1070)
Caused: org.openide.util.RequestProcessor$SlowItem: task failed due to: java.lang.NullPointerException
        at org.openide.util.RequestProcessor.post(RequestProcessor.java:292)
        at org.netbeans.modules.profiler.heapwalk.model.BrowserUtils.performTask(BrowserUtils.java:238)
        at org.netbeans.modules.profiler.heapwalk.model.BrowserUtils$1.run(BrowserUtils.java:204)
        at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:209)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
        at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:117)
        at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:269)
        at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:184)
        at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:174)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:169)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:161)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:122)