This class reads an xml stream and loads the objects in it into an IEnumerable[IBusinessObject]. It will update existing objects. For example, if you are deserialising an object from an xml stream that exists in your data store, it will load the object from the data store and update its properties from the xml stream. It won't persist after this. If the object does not exist in the data store then it will instantiate the object and set up its properties as a new object, ready to persist.