How should I build a multi-language help center? [duplicate]

This question already has an answer here:

• How to internationalize a Java web application? 3 answers
• How to implement internationalization in java 4 answers

I’d like to build a help center for my app like this one: https://stackoverflow.com/help

But in addition, I want it to be multi-language so I wonder if there is a way to iterate and search over a language file like messages.en-US, messages.fr-FR, etc.? If yes, how? If no, how should I proceed to do what I want?