notFoundCounter() is not correct when using  Slf4jConnectionPoolMonitorImpl 

If Slf4jConnectionPoolMonitorImpl is used the value of notFoundCounter will not be correct.
The problem is that incOperationFailure does not call super implementation in case of NotFoundException. 
It should not log it - at least it is not a warning but the super implementation should be called to update the counter returned by notFoundCounter() method.