java.lang.NullPointerException at com.sun.tools.javac.comp.MemberEnter$Synthesizer.visit(MemberEnter.java:1707) at com.sun.tools.javac.comp.MemberEnter$9.getModelType(MemberEnter.java:1689) at com.sun.tools.javac.code.Symbol$ClassSymbol.getSuperclass(Symbol.java:1074) at com.sun.tools.javac.code.Types$20.visitClassType(Types.java:2312) at com.sun.tools.javac.code.Types$20.visitClassType(Types.java:2301) at com.sun.tools.javac.code.Type$ClassType.accept(Type.java:763) at com.sun.tools.javac.code.Types$UnaryVisitor.visit(Types.java:4511) at com.sun.tools.javac.code.Types.supertype(Types.java:2298) at com.sun.tools.javac.code.Types$15.visitClassType(Types.java:1957) at com.sun.tools.javac.code.Types$15.visitClassType(Types.java:1946) at com.sun.tools.javac.code.Type$ClassType.accept(Type.java:763) at com.sun.tools.javac.code.Types$DefaultTypeVisitor.visit(Types.java:4430) at com.sun.tools.javac.code.Types.asSuper(Types.java:1943) at com.sun.tools.javac.code.Types$6.visitClassType(Types.java:920) at com.sun.tools.javac.code.Types$6.visitClassType(Types.java:842) at com.sun.tools.javac.code.Type$ClassType.accept(Type.java:763) at com.sun.tools.javac.code.Types$DefaultTypeVisitor.visit(Types.java:4430) at com.sun.tools.javac.code.Types.isSubtype(Types.java:838) at com.sun.tools.javac.code.Types.isSubtype(Types.java:808) at com.sun.tools.javac.code.Types.isSubtypeUncheckedInternal(Types.java:761) at com.sun.tools.javac.code.Types.isSubtypeUnchecked(Types.java:745) at com.sun.tools.javac.code.Types.isSubtypeUncheckedInternal(Types.java:759) at com.sun.tools.javac.code.Types.isSubtypeUnchecked(Types.java:745) at com.sun.tools.javac.code.Types.isConvertible(Types.java:303) at com.sun.tools.javac.code.Types.isAssignable(Types.java:2158) at com.sun.tools.javac.code.Types.isAssignable(Types.java:2121) at com.sun.tools.javac.model.JavacTypes.isAssignable(JavacTypes.java:107) at org.netbeans.modules.java.source.matching.CopyFinder.scan(CopyFinder.java:379) at org.netbeans.modules.java.source.matching.CopyFinder.scan(CopyFinder.java:591) at org.netbeans.modules.java.source.matching.CopyFinder.checkListsWithMultistatementTrees(CopyFinder.java:711) at org.netbeans.modules.java.source.matching.CopyFinder.checkListsWithMultistatementTrees(CopyFinder.java:743) at org.netbeans.modules.java.source.matching.CopyFinder.checkLists(CopyFinder.java:619) at org.netbeans.modules.java.source.matching.CopyFinder.visitMethodInvocation(CopyFinder.java:610) at org.netbeans.modules.java.source.matching.CopyFinder.visitMethodInvocation(CopyFinder.java:120) at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1477) at com.sun.source.util.TreeScanner.scan(TreeScanner.java:77) at org.netbeans.modules.java.source.matching.CopyFinder.doSuperScan(CopyFinder.java:578) at org.netbeans.modules.java.source.matching.CopyFinder.superScan(CopyFinder.java:570) at org.netbeans.modules.java.source.matching.CopyFinder.scan(CopyFinder.java:465) at org.netbeans.modules.java.source.matching.CopyFinder.scan(CopyFinder.java:318) at org.netbeans.modules.java.source.matching.CopyFinder.internalComputeDuplicates(CopyFinder.java:185) at org.netbeans.api.java.source.matching.Matcher.match(Matcher.java:189) at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.doComputeHints(HintsInvoker.java:551) at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHintsImpl(HintsInvoker.java:294) at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHints(HintsInvoker.java:239) at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHints(HintsInvoker.java:209) at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHints(HintsInvoker.java:182) at org.netbeans.modules.java.hints.spiimpl.hints.HintsInvoker.computeHints(HintsInvoker.java:149) at org.netbeans.modules.java.hints.spiimpl.hints.HintsTask.run(HintsTask.java:114) at org.netbeans.modules.java.hints.spiimpl.hints.HintsTask.run(HintsTask.java:83) at org.netbeans.modules.java.source.JavaSourceAccessor$CancelableTaskWrapper.run(JavaSourceAccessor.java:298) at org.netbeans.modules.parsing.impl.TaskProcessor.callParserResultTask(TaskProcessor.java:568) at org.netbeans.modules.parsing.impl.TaskProcessor$CompilationJob.run(TaskProcessor.java:744) 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:1423) at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2033)