I've made a little java application, with a very basic server. It's just a few classes and works at a pretty low level, using main, and manually opening sockets. It also uses a very simple custom protocol.
It works great on localhost, and I'm ready to deploy it to a server so I can start using the application from locations other than my LAN.
However, I can't find anywhere to host the darn thing. Ideally I'd like to find a service where I could upload an executable jar, have whatever port I want open, and then just run the executable. An ideal service would also make it easy for me to upload a new version of the jar as I improve upon the server. It needn't be free, but this application is going to have at most about 4 concurrent users, so I don't care about scalability, and wouldn't like to pay an exorbitant price for hosting. In the ballpark of $10 per month would be okay.
I've looked into services like Heroku, and a couple others, but all require you to be using Maven, or J2EE, JSP, whatever. I'm not using any of those, just good old public static void main(String[] args).
Would it be worth my while to adapt my application to fit one of those? Will that be complicated by the fact that I want to use a custom protocol?