CKFinder - how the file uploading works internally

Hi, I am trying to figure out the internal process of how the file uploading works with java integration.

I mean the exact process or if you can provide a java code sample. What I found out so far is that I don't see the file(part of it) during the uploading, which maybe means that is first uploaded to a temp directory and after copied to the desired directory. Our company needs to understand the process, because we make some file synchronizations between servers and need info for every system which plays with files.

Andrey