com.sun.jdi.IncompatibleThreadStateException
   at com.sun.tools.jdi.ThreadReferenceImpl.privateFrames(ThreadReferenceImpl.java:436)
   at com.sun.tools.jdi.ThreadReferenceImpl.frame(ThreadReferenceImpl.java:355)
   at org.netbeans.modules.debugger.jpda.jdi.ThreadReferenceWrapper.frame(ThreadReferenceWrapper.java:165)
   at org.netbeans.modules.debugger.jpda.actions.StepActionProvider.setLastOperation(StepActionProvider.java:512)
   at org.netbeans.modules.debugger.jpda.actions.StepActionProvider.setLastOperation(StepActionProvider.java:502)
   at org.netbeans.modules.debugger.jpda.actions.StepActionProvider.exec(StepActionProvider.java:367)
   at org.netbeans.modules.debugger.jpda.util.Operator$1.run(Operator.java:444)
   at java.lang.Thread.run(Thread.java:722)