Java Development Tools

All,

For my current project, I'm investigating the possibility to add autosave functionality to an (new) application. Is there perhaps anybody on the JDeveloper and ADF forum who already tried to implement such a functionality?
(JDeveloper 11.1.2.3.0 - ADF BC - ADF Faces Rich)

First question that rise up:
1) How to handle validation on the page?
2) Is it intended/needed to change the database tables design? (eg: less required field)
3) How/when to trigger a save call?
4) How to handle errors?

For the record: are there any plans on integrating autosave functionality to futuristic versions?

Thanks in advance,

Koen Verhulst