- A strong API for constructing validation rules exists in org.springframework.rules. This is applied in Spring Rich Client to drive declarative, as-you-type validation of form fields corresponding to domain object properties.
Areas needing development:
- The validation error reporting portion of this module in rules.reporting is not fully developed and somewhat weak at present.
- Client side validation for web apps is currently not supported.
- Spring MVC integration has not been developed at present.
In summary, it's not ready for out-of-the-box consumption in a Spring webapp. It's possible to take the base rules API, devleop the client side piece and the Spring MVC piece, but obviously that would provide some infrastructure development effort on your part. While this is on the rules road map, currently other things like Spring 1.2 are taking priority (so in other words, I wouldn't expect anything too soon here.)
Hope this helps!
Core Spring Development Team