Djeneric is a 4GL style development environment built on both RAD and MDA design principles. Using Djeneric you can build and customize an application in minutes, or you can apply MDA to mission critical application systems. Best of all: it's free, open source and 'no strings attached'.
Easy as 1-2-3: Create your database model with the Modeler, Define your application in terms of object usage (the view) and run it without compilation.
Djeneric is the ultimate prototyping tool for Java: changes to the model and view are visible instantaneous (just hit refresh)
Djeneric is flexible and extendable: add custom Java classes to your application for functionality outside the 4GL box. You can have the best of both 4GL and 3GL