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$ClassSymbol.getSuperclass(Symbol.java:963)
   at org.netbeans.modules.java.hints.ExportNonAccessibleElement.visitType(ExportNonAccessibleElement.java:222)
   at org.netbeans.modules.java.hints.ExportNonAccessibleElement.visitType(ExportNonAccessibleElement.java:92)
   at com.sun.tools.javac.code.Symbol$ClassSymbol.accept(Symbol.java:1229)
   at org.netbeans.modules.java.hints.ExportNonAccessibleElement.run(ExportNonAccessibleElement.java:113)
   at org.netbeans.modules.java.hints.legacy.spi.RulesManager$WorkerImpl.createErrors(RulesManager.java:411)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.runHint(HintsInvoker.java:810)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.access$400(HintsInvoker.java:112)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker$ScannerImpl.runAndAdd(HintsInvoker.java:669)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker$ScannerImpl.scan(HintsInvoker.java:688)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker$ScannerImpl.scan(HintsInvoker.java:622)
   at com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:91)
   at com.sun.source.util.TreeScanner.scan(TreeScanner.java:106)
   at org.netbeans.api.java.source.support.CancellableTreePathScanner.scan(CancellableTreePathScanner.java:103)
   at com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:114)
   at com.sun.source.util.TreeScanner.visitClass(TreeScanner.java:188)
   at com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:782)
   at com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:72)
   at org.netbeans.api.java.source.support.CancellableTreePathScanner.scan(CancellableTreePathScanner.java:94)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker$ScannerImpl.scan(HintsInvoker.java:694)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker$ScannerImpl.scan(HintsInvoker.java:622)
   at com.sun.source.util.TreeScanner.scan(TreeScanner.java:106)
   at org.netbeans.api.java.source.support.CancellableTreePathScanner.scan(CancellableTreePathScanner.java:103)
   at com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:114)
   at com.sun.source.util.TreeScanner.visitCompilationUnit(TreeScanner.java:145)
   at com.sun.tools.javac.tree.JCTree$JCCompilationUnit.accept(JCTree.java:563)
   at com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:53)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker$ScannerImpl.scan(HintsInvoker.java:713)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHintsImpl(HintsInvoker.java:257)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHints(HintsInvoker.java:240)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHints(HintsInvoker.java:210)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHints(HintsInvoker.java:183)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHints(HintsInvoker.java:150)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsTask.run(HintsTask.java:137)
   at org.netbeans.modules.java.hints.spiimpl.hints.HintsTask.run(HintsTask.java:88)
   at org.netbeans.modules.java.source.JavaSourceAccessor$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)