com.sun.jdi.InternalException: Unexpected JDWP Error: 502
        at com.sun.tools.jdi.JDWPException.toJDIException(JDWPException.java:47)
        at com.sun.tools.jdi.ObjectReferenceImpl.invokeMethod(ObjectReferenceImpl.java:379)
        at org.netbeans.modules.debugger.jpda.expr.TreeEvaluator.invokeVirtual(TreeEvaluator.java:164)
        at org.netbeans.modules.debugger.jpda.JPDADebuggerImpl.invokeMethod(JPDADebuggerImpl.java:844)
        at org.netbeans.modules.debugger.jpda.models.AbstractObjectVariable.getToStringValue(AbstractObjectVariable.java:315)
        at org.netbeans.modules.debugger.jpda.models.AbstractObjectVariable.getToStringValue(AbstractObjectVariable.java:285)
        at org.netbeans.modules.debugger.jpda.projects.ToolTipAnnotation.run(ToolTipAnnotation.java:166)
        at org.openide.util.RequestProcessor$Task.run(RequestProcessor.java:561)
        at org.openide.util.RequestProcessor$Processor.run(RequestProcessor.java:986)