Currently MongoConnectionException contains a Generation field that is created as a workaround to pass a poolGeneration to the exceptionHandling logic.

This logic works as expected only when we call error handling on handshake exception. In this case it will always return false.

Also, MongoConnectionException is used in a lot of places in the code, so it's not the best way to add a field that will be assigned only in very limited place.

So this logic should be reconsidered.