Okay I employed some help from a colleague to understand this. It turned out to be a simple and slightly embarrassing solution. Somewhere down the line I must have installed this 4J executable and for some reason it was set to open on start-up (not sure if this was a fault of my own or the Mac's).
For anyone else who has an issue with unwanted applications starting up upon log in, you can solve them fairly easily by hitting:
Apple icon (Top left) -> System Preferences -> Users & Groups -> Login Items
Then simply hit minus (-) to be rid of them! You may find some more unwanted applications on there like iTunes Helper or (in my instance) Flu.x which was being loaded 4 times... A nice way to speed up the mac on start up as well.
Hope this helps anyone who has similar problems.