How to use XI Value Mapping from Java Mapping

I'm using a conversion units table stored in external xml document but i'd like to avoid external files in xi mappings so i think the best option is replace this file for a value mapping. Is this possible?

If it's possible, how can i do to access these key-value pairs from within java code?

And is it possible to access a value mapping from a program running outside xi?

Thanks in advance.

Joaquin Carballo