I'm not too sure about the rest of your post, but for converting beans to/from XML, I used betwixt on a project and it worked well for me. You can check it out here:
If I understand correctly you want a tool to take your tables into xml mapping.....I use a tool called middlegen. There isn't much docs on it but its not hard to figure out. If by chance you are using hibernate I use a tool called hbm2java to convert xml mapping into beans.