java.lang.NullPointerException
   at org.openide.nodes.EntrySupport$Default.updateOrder(EntrySupport.java:450)
   at org.openide.nodes.EntrySupport$Default.setEntries(EntrySupport.java:344)
   at org.openide.nodes.Children$Keys$2.run(Children.java:1505)
   at org.openide.util.Mutex$1Exec.run(Mutex.java:1239)
   at org.openide.nodes.Children$ProjectManagerDeadlockDetector.execute(Children.java:1812)
   at org.openide.util.Mutex.postRequest(Mutex.java:1245)
   at org.openide.util.Mutex.postRequest(Mutex.java:1209)
   at org.openide.util.Mutex.postWriteRequest(Mutex.java:582)
   at org.openide.nodes.Children$Keys.applyKeys(Children.java:1514)
   at org.openide.nodes.Children$Keys.setKeys(Children.java:1458)
   at org.netbeans.spi.project.ui.support.NodeFactorySupport$DelegateChildren.access$1100(NodeFactorySupport.java:133)
   at org.netbeans.spi.project.ui.support.NodeFactorySupport$DelegateChildren$RunnableImpl.run(NodeFactorySupport.java:331)
   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:125)
   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)