java.util.ConcurrentModificationException: Current owner: [org.netbeans.modules.java.source.parsing.ProxyFileManager.clearOwnerThread(ProxyFileManager.java:539), org.netbeans.modules.java.source.parsing.ProxyFileManager.list(ProxyFileManager.java:210), com.sun.tools.javac.jvm.ClassReader.fillIn(ClassReader.java:2561), com.sun.tools.javac.jvm.ClassReader.complete(ClassReader.java:2234), com.sun.tools.javac.code.Symbol.complete(Symbol.java:422), com.sun.tools.javac.comp.Enter.visitTopLevel(Enter.java:339), com.sun.tools.javadoc.JavadocEnter.visitTopLevel(JavadocEnter.java:78), com.sun.tools.javac.tree.JCTree$JCCompilationUnit.accept(JCTree.java:457), com.sun.tools.javac.comp.Enter.classEnter(Enter.java:298), com.sun.tools.javac.comp.Enter.classEnter(Enter.java:312), com.sun.tools.javac.comp.Enter.complete(Enter.java:708), com.sun.tools.javac.main.JavaCompiler.complete(JavaCompiler.java:979), com.sun.tools.javac.main.JavaCompiler.enterTrees(JavaCompiler.java:945), org.netbeans.modules.java.hints.spiimpl.Utilitie
   at org.netbeans.modules.java.source.parsing.ProxyFileManager.checkSingleOwnerThread(ProxyFileManager.java:529)
   at org.netbeans.modules.java.source.parsing.ProxyFileManager.list(ProxyFileManager.java:184)
   at com.sun.tools.javac.jvm.ClassReader.fillIn(ClassReader.java:2561)
   at com.sun.tools.javac.jvm.ClassReader.complete(ClassReader.java:2234)
   at com.sun.tools.javac.code.Symbol.complete(Symbol.java:422)
   at com.sun.tools.javac.jvm.ClassReader.completeOwners(ClassReader.java:2246)
   at com.sun.tools.javac.jvm.ClassReader.complete(ClassReader.java:2219)
   at com.sun.tools.javac.code.Symbol.complete(Symbol.java:422)
   at com.sun.tools.javac.code.Symbol$ClassSymbol.complete(Symbol.java:833)
   at com.sun.tools.javac.code.Symbol$ClassSymbol.members(Symbol.java:778)
   at com.sun.tools.javac.jvm.ClassReader$AnnotationDeproxy.findAccessMethod(ClassReader.java:1595)
   at com.sun.tools.javac.jvm.ClassReader$AnnotationDeproxy.deproxyCompound(ClassReader.java:1585)
   at com.sun.tools.javac.jvm.ClassReader$AnnotationDeproxy.deproxyCompoundList(ClassReader.java:1574)
   at com.sun.tools.javac.jvm.ClassReader$AnnotationCompleter.enterAnnotation(ClassReader.java:1764)
   at com.sun.tools.javac.comp.Annotate.flush(Annotate.java:109)
   at com.sun.tools.javac.comp.Annotate.enterDone(Annotate.java:101)
   at com.sun.tools.javac.comp.Enter.complete(Enter.java:734)
   at com.sun.tools.javac.main.JavaCompiler.complete(JavaCompiler.java:979)
   at com.sun.tools.javac.main.JavaCompiler.enterTrees(JavaCompiler.java:945)
   at com.sun.tools.javac.api.JavacTaskImpl.enter(JavacTaskImpl.java:369)
   at com.sun.tools.javac.api.JavacTrees.getAttrContext(JavacTrees.java:258)
   at com.sun.tools.javac.api.JavacTrees.getScope(JavacTrees.java:217)
   at com.sun.tools.javac.api.JavacTrees.getScope(JavacTrees.java:84)
   at org.netbeans.api.java.source.TreeUtilities.scopeFor(TreeUtilities.java:501)
   at org.netbeans.modules.debugger.jpda.projects.EditorContextImpl$ParseExpressionTask.run(EditorContextImpl.java:2154)
   at org.netbeans.modules.debugger.jpda.projects.EditorContextImpl.parseExpression(EditorContextImpl.java:2081)
   at sun.reflect.NativeMethodAccessorImpl.invoke0(NativeMethodAccessorImpl.java:0)
   at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
   at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
   at java.lang.reflect.Method.invoke(Method.java:601)
   at org.netbeans.modules.debugger.jpda.EditorContextBridge.parseExpression(EditorContextBridge.java:130)
   at org.netbeans.modules.debugger.jpda.expr.TreeEvaluator.evaluate(TreeEvaluator.java:183)
   at org.netbeans.modules.debugger.jpda.JavaEvaluator.evaluateIn(JavaEvaluator.java:144)
   at org.netbeans.modules.debugger.jpda.JavaEvaluator.evaluate(JavaEvaluator.java:92)
   at org.netbeans.modules.debugger.jpda.expr.EvaluatorExpression$AssociatedExpression.evaluate(EvaluatorExpression.java:90)
   at org.netbeans.modules.debugger.jpda.expr.EvaluatorExpression.evaluate(EvaluatorExpression.java:73)
   at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluateGeneric(JPDADebuggerImpl.java:896)
   at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluateIn(JPDADebuggerImpl.java:765)
   at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluateIn(JPDADebuggerImpl.java:788)
   at org.netbeans.modules.debugger.jpda.models.WatchesModel$JPDAWatchEvaluating.getValue(WatchesModel.java:433)
   at org.netbeans.modules.debugger.jpda.models.WatchesModel$JPDAWatchEvaluating.getType(WatchesModel.java:391)
   at org.netbeans.modules.debugger.jpda.ui.models.VariablesTreeModelFilter.getFilter(VariablesTreeModelFilter.java:652)
   at org.netbeans.modules.debugger.jpda.ui.models.VariablesTreeModelFilter.access$400(VariablesTreeModelFilter.java:124)
   at org.netbeans.modules.debugger.jpda.ui.models.VariablesTreeModelFilter$3.run(VariablesTreeModelFilter.java:361)
   at org.netbeans.modules.debugger.jpda.ui.models.VariablesTreeModelFilter.run(VariablesTreeModelFilter.java:259)
   at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:1454)
   at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:2048)