The Graphical Editing Framework (GEF) provides technology to create rich graphical application. It is currently developed in two streams, namely:
The original project components Draw2d 3.x, GEF (MVC) 3.x, and Zest 1.x are still maintained but will not be developed further. Our main development effort is instead spent on the next generation components in terms of GEF4.
September 25, 2015 - Release 3.10.1 is available as part of the Mars.1 simultaneous release, including Draw2d 3.10.1, GEF (MVC) 3.10.1, and Zest 1.6.1, as well as GEF4 0.2.0 (incompatible to 0.1.0, not contributed to sim-rel). Follow the Download link to obtain it. For further information about included features or bug fixes, please refer to the New and Noteworthy (3.10.1) page.
While the bulk of information about the GEF project can be found here, you may also consider the GEF Wiki as a source for further information.