Correct way to obtain element info?

I need to obtain the bounding box of each text element in an SVG document.
I've tried searching around for how to do this, but, don't find much (or a
lot of unrelated stuff).

I thought it might be as simple as writing a batik extension, such that as
an SVG document was read in from a file (or even when rendered with using
the rasterizer code), my extension would be called with the element.  Kind
of like a SAX parser, where I could tie in for regular XML processing.  I'd
use a SAX processor, but, of course, the SVG actually needs to be processed
9transofrms calculated into bounds), not merely parsed.

Any help would be appreciated.