If I have a large XML from other external application.

I have the XML on the server i.e. my local machine. the location is something like

C:\\Documents and Settings\\rahul_arora\\Desktop\\book.xml

Now I want this to be utilised in SFDC. All the examples to read the XML have the XML code converted to string and then instantiate the XMLStreamReader.

How do I do in my case. Kindly suggest the elaborated approach.