java.lang.NullPointerException
   at com.sun.tools.javac.comp.Attr.checkBase(Attr.java:821)
   at com.sun.tools.javac.comp.Attr.checkIntersection(Attr.java:4027)
   at com.sun.tools.javac.comp.Attr.visitBinary(Attr.java:3127)
   at com.sun.tools.javac.tree.JCTree$JCBinary.accept(JCTree.java:1774)
   at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:611)
   at com.sun.tools.javac.comp.Attr.attribExpr(Attr.java:629)
   at com.sun.tools.javac.comp.Attr.attribArgs(Attr.java:680)
   at com.sun.tools.javac.comp.Attr.visitApply(Attr.java:1845)
   at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1463)
   at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:611)
   at com.sun.tools.javac.comp.Attr.attribExpr(Attr.java:629)
   at com.sun.tools.javac.comp.Attr.attribLazyConstantValue(Attr.java:786)
   at com.sun.tools.javac.code.Symbol$VarSymbol$2.call(Symbol.java:1069)
Caused: java.lang.AssertionError: java.lang.NullPointerException
   at com.sun.tools.javac.code.Symbol$VarSymbol.getConstValue(Symbol.java:1105)
   at com.sun.tools.javac.comp.Attr.visitVarDef(Attr.java:1102)
   at com.sun.tools.javac.tree.JCTree$JCVariableDecl.accept(JCTree.java:850)
   at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:611)
   at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:656)
   at com.sun.tools.javac.comp.Attr.attribStats(Attr.java:672)
   at com.sun.tools.javac.comp.Attr.visitBlock(Attr.java:1163)
   at org.netbeans.lib.nbjavac.services.NBAttr.visitBlock(NBAttr.java:82)
   at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:907)
   at com.sun.tools.javac.comp.Attr.attribTree(Attr.java:611)
   at com.sun.tools.javac.comp.Attr.attribStat(Attr.java:656)
   at com.sun.tools.javac.comp.Attr.attribStatToTree(Attr.java:461)
   at com.sun.tools.javac.api.JavacTrees.attribStatToTree(JavacTrees.java:874)
   at com.sun.tools.javac.api.JavacTrees.getAttrContext(JavacTrees.java:842)
   at com.sun.tools.javac.api.JavacTrees.getScope(JavacTrees.java:724)
   at com.sun.tools.javac.api.JavacTrees.getScope(JavacTrees.java:123)
   at org.netbeans.modules.java.hints.introduce.IntroduceHint.computeError(IntroduceHint.java:440)
   at org.netbeans.modules.java.hints.introduce.IntroduceHint.run(IntroduceHint.java:367)
   at org.netbeans.modules.java.hints.introduce.IntroduceHint.run(IntroduceHint.java:160)
   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$RunnableAdapter.call(Executors.java:471)
   at java.util.concurrent.FutureTask.run(FutureTask.java:262)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1432)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2042)