org.netbeans.api.debugger.jpda.InvalidExpressionException: No current context (stack frame)
        at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluateIn(JPDADebuggerImpl.java:865)
        at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluateIn(JPDADebuggerImpl.java:762)
        at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluate(JPDADebuggerImpl.java:393)
        at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.evaluate(JPDADebuggerImpl.java:369)
        at org.netbeans.modules.debugger.jpda.models.AbstractObjectVariable.evaluate(AbstractObjectVariable.java:521)
Caused: java.lang.reflect.InvocationTargetException
        at sun.reflect.NativeMethodAccessorImpl.invoke0(NativeMethodAccessorImpl.java:0)
        at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
        at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
        at java.lang.reflect.Method.invoke(Method.java:597)
        at org.netbeans.modules.debugger.jpda.ui.models.VariablesFormatterFilter.getChildren(VariablesFormatterFilter.java:167)
        at org.netbeans.modules.debugger.jpda.ui.models.VariablesTreeModelFilter.getChildren(VariablesTreeModelFilter.java:205)
        at org.netbeans.spi.viewmodel.Models$CompoundTreeModel.getChildren(Models.java:699)
        at org.netbeans.spi.viewmodel.Models$CompoundModel.getChildren(Models.java:3145)
        at org.netbeans.modules.viewmodel.TreeModelNode$TreeModelChildren.evaluateLazily(TreeModelNode.java:805)
        at org.netbeans.modules.viewmodel.TreeModelNode$LazyEvaluator.run(TreeModelNode.java:1253)
        at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:573)
        at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:1005)