Client and Server Side rules engines?

Question

I'm looking for Java rules engine options that will allow me to use the same rules in a server side backend, a GWT frontend, and JavaME apps. I'd also love to hear about the pitfalls of attempting to do such.

The motivation is a push to use a rules engine in a server side code base that I am concerned may cause a schism between validation and business logic that is replicated between the clients and server side. We need to support really slow links and intermittent connectivity so always calling the back end to execute the rules isn't a preferred options.

Thanks.

Answer 1

SmartGWT has a client- and server-side validation engine covering typical form validation use cases:

http://www.smartclient.com/smartgwtee/showcase/#data_integration_form_validation

The server side of the engine could ship with a JME application as well.

Conditional validation (eg rules like value must be >5 if other field is non-null) with both client and server-side enforcement is part of the upcoming 2.1 release.