java.lang.NullPointerException
   at com.sun.tools.javac.comp.TypeEnter$AbstractHeaderPhase$Synthesizer.visit(TypeEnter.java:551)
   at com.sun.tools.javac.comp.TypeEnter$AbstractHeaderPhase$1.getModelType(TypeEnter.java:533)
   at com.sun.tools.javac.code.Symbol$ClassSymbol.getSuperclass(Symbol.java:1143)
   at com.sun.tools.javac.code.Symbol$ClassSymbol.getSuperclass(Symbol.java:963)
   at org.netbeans.modules.java.navigation.ElementScanningTask.createHtmlHeader(ElementScanningTask.java:425)
   at org.netbeans.modules.java.navigation.ElementScanningTask.element2description(ElementScanningTask.java:266)
   at org.netbeans.modules.java.navigation.ElementScanningTask.addMembers(ElementScanningTask.java:228)
   at org.netbeans.modules.java.navigation.ElementScanningTask.runImpl(ElementScanningTask.java:147)
   at org.netbeans.modules.java.navigation.ElementScanningTask.run(ElementScanningTask.java:105)
   at org.netbeans.modules.java.navigation.ElementScanningTask.run(ElementScanningTask.java:86)
   at org.netbeans.modules.java.source.JavaSourceAccessor$CancelableTaskWrapper.run(JavaSourceAccessor.java:298)
   at org.netbeans.modules.parsing.impl.TaskProcessor.callParserResultTask(TaskProcessor.java:584)
   at org.netbeans.modules.parsing.impl.TaskProcessor$RequestPerformer.run(TaskProcessor.java:809)
   at org.openide.util.lookup.Lookups.executeWith(Lookups.java:304)
   at org.netbeans.modules.parsing.impl.TaskProcessor$RequestPerformer.execute(TaskProcessor.java:725)
   at org.netbeans.modules.parsing.impl.TaskProcessor$CompilationJob.run(TaskProcessor.java:686)
   at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
   at java.util.concurrent.FutureTask.run(FutureTask.java:266)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1443)
   at org.netbeans.modules.openide.util.GlobalLookup.execute(GlobalLookup.java:68)
   at org.openide.util.lookup.Lookups.executeWith(Lookups.java:303)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2058)