Which programing language?
With Java you can use for example jdom to read an xml file to a Document object. You can then parse this Document to create your own object. No need to serialize the object to xml previously.
Also, with xstream you can read an xml file and create an object. There is no need to serialize before, but you must create the class before.
With JAXB you can also create an object from an xml file, but in this case you must create the xml schema before.
In other languages I suppose there are similar features.