There is no best. What CAN you use? If FTP is an option (and make it SFTP) then of course go for that, then you don't have to be bothered by the clunky HTTP file upload.
> What should be the Application interface for data uploading module
How about a proper existing SFTP client? There is absolutely no reason at all why that should be anything Java related.
> To resolve Memory Heap size errors we are using cronjob to restart web server, is it OK ? OR there is some other batter solutions for this.
How about finding and solving the source of your memory leaks?
Thanks Gimbal2 for your valuable advice. Im serching net for the following:-
- How to find memory leaks.
com.jcraft.jsch package to upload files along with a database entry for uploaded file record.
Note that the JSCH api is poorly documented but the (source?) download package contains example programs and unit tests which demonstrate how to use all the features.