session lost in MultipartRequest

I'm adding in file uploading features to my application. I'm having a problem that whenever I use enctype ="multipart/form-data" in my jsp page, the session will become null. It works fine when I remove the above enctype, but the file uploading no longer function. Do you have any idea how to over come this problem? Any suggestion will be highly appreci开发者_开发百科ated. Thanks a lot.

From your description it seems that not the session is null but you don't get the attributes from the session in the way you used to.

Try something like Apache Commons Fileupload to have a quite easy solution.