Best way to store text in an application / game without 'hardcoding'?

While I'm sure this question has probably been asked before, my research has left me fruitless. Thus, I've decided to pose the question: "What is the best way to store text in an application / game without 'hardcoding'?".

I've dabbled with Android in the past, and was quite fond of the way it used xml to store String resources. However, I'm currently developing a desktop game based on the libGDX and don't have such functionality natively available to me (as far as I'm aware, at least). I guess I could define class constants for the various Strings, but I feel like that would be a 'smelly' solution...

Any guidance would be greatly, greatly appreciated! Thanks!