I am digging int xdoclet nd hibernate
but can u please tell how to do this for a real world scenario
like user login and upload images
where schema will be

*table users*
userid
password*
image table*
userid (foriegn key refers userid of users)
imagename


*Two classes user and image can u please tell how can i modify these two classes to include mapping *

If i can catch the funda of this , bcs i already started with hibernate and urgently want to include ths into our project

Look at one (or more) of the examples and demos around the net.
We list quite a few (where struts resume may fit the bill).
See http://hibernate.org/27.html as a start.