Mostly Java and Swing. Knowing Grails helps you pick up the build workflow much faster but it is not a requirement.
Griffon is inspired by Grails. It follows Grails' build process closely but at runtime it's a different matter, as Griffon injects its own distinctiveness.
Anil Vupputuri wrote:How fast the development can be, comparable to JSF? What makes Griffon to outclass similar frameworks in market?
Comparing to JSF is not a good comparison to start with: JSF = web; Griffon = desktop/RIA.
Griffon "outclasses" similar frameworks by:
- leveraging more than 5 years of Grails knowledge and development
- following recent approaches to better productivity: Convention over Configuration, DRY, automated tasks, testing supported out of the box
- using the Groovy language both as glue language and declarative 'markup' (no more XML pain).
- a growing plugin community