java.lang.NullPointerException
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.visitTypeParameter(TreeInfo.java:503)
        at com.sun.tools.javac.tree.JCTree$JCTypeParameter.accept(JCTree.java:1874)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.scan(TreeInfo.java:484)
        at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:57)
        at com.sun.tools.javac.tree.TreeScanner.visitMethodDef(TreeScanner.java:86)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.visitMethodDef(TreeInfo.java:496)
        at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:657)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.scan(TreeInfo.java:484)
        at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:57)
        at com.sun.tools.javac.tree.TreeScanner.visitClassDef(TreeScanner.java:80)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.visitClassDef(TreeInfo.java:492)
        at com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:588)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.scan(TreeInfo.java:484)
        at com.sun.tools.javac.tree.TreeScanner.visitNewClass(TreeScanner.java:202)
        at com.sun.tools.javac.tree.JCTree$JCNewClass.accept(JCTree.java:1350)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.scan(TreeInfo.java:484)
        at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:57)
        at com.sun.tools.javac.tree.TreeScanner.visitApply(TreeScanner.java:195)
        at com.sun.tools.javac.tree.JCTree$JCMethodInvocation.accept(JCTree.java:1300)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.scan(TreeInfo.java:484)
        at com.sun.tools.javac.tree.TreeScanner.visitExec(TreeScanner.java:171)
        at com.sun.tools.javac.tree.JCTree$JCExpressionStatement.accept(JCTree.java:1146)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.scan(TreeInfo.java:484)
        at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:57)
        at com.sun.tools.javac.tree.TreeScanner.visitBlock(TreeScanner.java:102)
        at com.sun.tools.javac.tree.JCTree$JCBlock.accept(JCTree.java:769)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.scan(TreeInfo.java:484)
        at com.sun.tools.javac.tree.TreeScanner.visitMethodDef(TreeScanner.java:89)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.visitMethodDef(TreeInfo.java:496)
        at com.sun.tools.javac.tree.JCTree$JCMethodDecl.accept(JCTree.java:657)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.scan(TreeInfo.java:484)
        at com.sun.tools.javac.tree.TreeScanner.scan(TreeScanner.java:57)
        at com.sun.tools.javac.tree.TreeScanner.visitClassDef(TreeScanner.java:80)
        at com.sun.tools.javac.tree.TreeInfo$1DeclScanner.visitClassDef(TreeInfo.java:492)
        at com.sun.tools.javac.tree.JCTree$JCClassDecl.accept(JCTree.java:588)
        at com.sun.tools.javac.tree.TreeInfo.declarationFor(TreeInfo.java:508)
        at com.sun.tools.javac.model.JavacElements.getTreeAndTopLevel(JavacElements.java:632)
        at com.sun.tools.javac.model.JavacElements.getDocComment(JavacElements.java:402)
        at org.netbeans.modules.java.editor.javadoc.JavadocImports$UnresolvedImportScanner.resolveElement(JavadocImports.java:450)
        at org.netbeans.modules.java.editor.javadoc.JavadocImports$UnresolvedImportScanner.visitExecutable(JavadocImports.java:429)
        at org.netbeans.modules.java.editor.javadoc.JavadocImports$UnresolvedImportScanner.visitExecutable(JavadocImports.java:416)
        at com.sun.tools.javac.code.Symbol$MethodSymbol.accept(Symbol.java:1339)
        at javax.lang.model.util.ElementScanner6.scan(ElementScanner6.java:139)
        at javax.lang.model.util.ElementScanner6.scan(ElementScanner6.java:129)
        at javax.lang.model.util.ElementScanner6.visitType(ElementScanner6.java:169)
        at org.netbeans.modules.java.editor.javadoc.JavadocImports$UnresolvedImportScanner.visitType(JavadocImports.java:437)
        at org.netbeans.modules.java.editor.javadoc.JavadocImports$UnresolvedImportScanner.visitType(JavadocImports.java:416)
        at com.sun.tools.javac.code.Symbol$ClassSymbol.accept(Symbol.java:859)
        at javax.lang.model.util.ElementScanner6.scan(ElementScanner6.java:139)
        at javax.lang.model.util.ElementScanner6.scan(ElementScanner6.java:129)
        at org.netbeans.modules.java.editor.javadoc.JavadocImports.computeUnresolvedImports(JavadocImports.java:86)
        at org.netbeans.modules.java.editor.imports.ComputeImports.computeCandidates(ComputeImports.java:128)
        at org.netbeans.modules.java.editor.imports.ComputeImports.computeCandidates(ComputeImports.java:104)
        at org.netbeans.modules.java.hints.errors.ImportClass.getCandidateFQNs(ImportClass.java:238)
        at org.netbeans.modules.java.hints.errors.ImportClass.run(ImportClass.java:141)
        at org.netbeans.modules.java.hints.infrastructure.CreatorBasedLazyFixList.compute(CreatorBasedLazyFixList.java:144)
        at org.netbeans.modules.java.hints.infrastructure.LazyHintComputation.run(LazyHintComputation.java:109)
        at org.netbeans.modules.java.hints.infrastructure.LazyHintComputation.run(LazyHintComputation.java:55)
        at org.netbeans.api.java.source.JavaSource$CompilationJob.run(JavaSource.java:1675)
        at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
        at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
        at java.util.concurrent.FutureTask.run(FutureTask.java:138)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:885)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:907)
        at java.lang.Thread.run(Thread.java:619)