Upload objects in folder amazon

I am trying to uploads objects in folder and i know there is no concept of real folder in amazon aws, I am doing this for file management purpose

For that i am POST Uploads to Amazon S3 (http://ift.tt/1MBhkVN) its working fine but the problem is that it only upload file to bucket like

bucket-demo
    -file-one.jpg
    -file-tow.png

but what i am trying to do is

bucket-demo
     /abc/                 <--folder
         file-one.png
         file tow.png

now i tried to put directory name after action link but doesnt work