Stop Xcode from opening developer files by default

Hi guys.

Up until this point, I have been using Sublime Text 3 for pretty much any of my development needs. I used it for Java, C and R (Assembly) but now wanted to get into OpenGL as a hobby. Being on a Mac, I was recommended Xcode, so I got from the App Store. My trouble is that Xcode for some reason decided "from now on, I will open any developer file (i.e. .java, .html etc etc)". I don't want that.

Yes, I am aware that I can right click a file and set the "default program" for that file type using the "Get Info" panel and then setting Sublime Text, but ideally, I want Xcode to not be the default go-to program for any file type I may work with. If possible, I'd like to find an option like the wireless networks: You drag and drop in your favorite order.

Many thanks