progress bar and timeout functionality for file upload

Hi,
I am uploading a file using commons file-upload.
I will upload the file on the server, do some processing on the file data, persist into database and then send a response back to user with file uploaded successfully with or without errors.
If error occurs i need to delete the file from the server and remove some rows from the database.

While uploading and processing the file on the server i need to show the user some modal dialog box which will give the progress bar or at least a gif image with "Processing..." kind of text. The important point, I need to show the dialog while Uploading and PROCESSING the file. I also need to timeout the upload request if uploading and processing takes more than 3 mins.

I am not sure how can i send a request on the server still show some dialog on client side while processing is going on server?
Any code will definitely help...

Thanks...

See https://coderanch.com/t/364667/Servlets/java/Inremediate-page-while-processing

Thanks a lot for the quick reply...
I think i am looking for this kind approach only but i need to show the main window too and on top of it i need to show this dialog (of maybe a small window) saying processing... and when this small window is open you should not able to go to the main window (modal functionality).
Can this can also be achieved?
Else i will use your approach showing an intermediate page...

thanks!!!