transfer a xml file from Android device to Java website by USB

I'm working on an Android application who work offline. What I want to do is when my user connects his phone/tablet to his computer, he can go to my website and upload an XML file generate by the Android application to my website and eventually populate the DB. Is it possible to do this? If it is, How can I do it (need explanations). Is it possible to specified in which folder the file-upload will open (into the android application folder who contains the XML files)?

There is another way to do this without connecting the device to the internet.

Thank you very much