I know guys you have plan to add GWT/Flex support in Roo 2.0.
But we do not want to wait :-) And we are building custom Web UI generation plugin for Dojo toolkit. It is way different with what you have now mixing JSPX/JSTL/Tiles2/SpringMVC and some Ajax'fing via Dojo. We build pure HTML Web 2.0 Dojo based reusable components for scaffolding backed by JSON-RPC exposed services.

The way we do it now is a bit cumbersome. We took standard JspMetadataListener & Co as an example and created custom DojoMetadataListener (with supported classes) which behaves very similar except it generated different output.

It works, but we have a lot of duplication code borrowed from original JspMetadataListener for doing stuff like implementing MetadataProvider and MetadataNotificationListener. I mean most of the operations like creating WebScaffoldMetadata are very similar between your JspMetadataListener, our DojoMetadataListener and (I guess) proposed GwtMetadataListener and FlexMetadataListener.

Do you guys have anything in mind in order to create something abstract to help develop custom UI Generators w/o doing much of the duplications? Or what ideas are?

Thanks!