My reply is slightly off-topic, but here's a small wiki for turning a Java application into a service using the NSSM service manager:
https://github.com/qzind/tray/wiki/windows-service
Note, this tutorial is specific to a project I maintain, but the steps can be adapted. The steps about %APPDATA% can be skipped, they're specific to the app and won't necessarily apply.
Finally, if your requirement is for the Java application to start on Login (not necessarily with the computer), then you can do this with a combination of standard Windows calls, such as using
mslinks to write a windows desktop shortcut (.lnk) to the
startup folder. Note, there are user-startup folders, common startup folders and you may need elevated security to write to the common location.