Dear Ludek,
Many thanks for your helpful reply and it makes my mind much more clear. Now my problem goes clear as "How to change XML connection property in runtime".
Just found one similar question as this at below address:
http://scn.sap.com/thread/1247885
In above topic, Ted used to said below:
"You can switch XML datasource by changing the connection info properties before running the document. So if the report remains unchanged but you just want a different datasource for the report, it'll be just doing replaceConnection as you would with any other data source type".
May I know where to find the JSP sample to show the code snippet about "switch XML datasource"?
Best Regards,
Rodney