When you first posted, I googled too and couldn't find anything useful.
But now when I google for "ofx specification" (which I didn't do before, I don't know why) I find a link to... the OFX specifications.
http://www.ofx.net/ofx/de_spec.asp
It says that as of OFX version 2.0, it's based on XML. I assume that means it's a dialect of XML. Java has an API that can process XML, as you know because you posted in this forum. So... yes.
And from that page you can download the specifications.