File Downloader Utility

We currently run a video service where users upload videos, which are then encoded by our service (similar to Youtube) and then stored in an AWS S3 bucket on the back end. Site visitors can stream these videos using our players, but they cannot download them. However, we want to give the account owner (the people who posted the videos) the ability to download the raw encoded videos from S3, but only the videos that belong specifically to them. Obviously different people logged in would see a different set of files. What we need is a cross platform Java or flash downloader tool which will allow a logged in user to download raw files from an S3 bucket in a controlled manner. In our MSSQL database would be a list of file ID numbers which belong to the user. When the account owner uses the downloader tool, they would see the list of files that belong to them. They could click on one or more to begin download, and it would be downloaded locally to their machine. After download is confirmed, our MSSQL database is updated that the file was successfully downloaded. More details attached..