@gabizou tx for your reply >1+ yr ago, and sorry for (very 
late follow-up …
So hot swapping from an IDE has significant limitations - it only really works great for changing a few lines in existing class, but you cannot really “dynamically develop” with it - say start your Minecraft server in the morning, then create a new mod, add new classes in, re-factor it, keep coding a mod all day long - all without ever restarting the server.
FYI I’ve meanwhile stopped working further on my GitHub - vorburger/HoTea: Plug-In framework with HOT Class reloading for dynamic script-like Java, as I’ve in a parallel life (day job work) eventually learnt more about OSGi, which is a much better foundation for this kind of thing - it has already solved the typical kind of problems one runs into with something like this like, dependencies and versioning and what not, and has a rich existing ecosystem around it.
GitHub - vorburger/ch.vorburger.minecraft.osgi: OSGi-based Minecraft Server plugins (spongepowered.org), just announced over on OSGi - a dynamic plugin reloader type mod useful for development, is my latest stab in this space.