Groovlet, GroovyServer Pages (GSP) frameworks are built on Java Servlet API. Unlike Struts and JSF, Groovy server isn't for all uses: it is simple alternate for coding server programs fast and easy. By Andrew Glover. IBM developerWorks.
Mimic markup languages like XML, HTML, Ant tasks, and GUIs, with frameworks like Swing; useful for fast prototyping; handy alternate to data binding frameworks when needing consumable markup fast. By Andrew Glover. IBM developerWorks.