Motivation
Green was initially developed to support the teaching of software development to beginning Computer Science & Engineering students. Having students learn about good software design, especially the use of design patterns, was paramount. Without a good sense of design, how could a student begin to write code (what would she be coding?)

The pedagogical goal of Green is to focus students on design rather than syntactic details. Green's round-trip capability enables students to move from a high-level design view to a low-level code view at any point in time: the class diagram view and the code view are simply different perspectives on the very same artefact.

Design
Green is a live round-tripping editor. It is a round-tripping editor because it allows you to generate (Java) code from a UML class diagram, and it also allows you to generate a diagram from (Java) code. It is a live round-tripping editor because the diagram is updated whenever the code is changed, and vice versa.

Eclipse project's Graphical Editing Framework (GEF) and its Java Development Tools (JDT) supply much of the framework underlying Green. Green itself provides a UML class diagram model, and extension points for supplying relationship semantics.

Green's live round-tripping is accomplished using Eclipse's Java Model and Abstract Syntax Tree, which provide the necessary data structures and tools for live representation of the static structure of Java programs. By focusing on static analysis of code, we have developed a tool that is very good for specific purpose, rather than one that works with all aspects of the software engineering process. The editor features a simple point-and-click interface. Right-clicking in the editor brings up a context menu that includes refactoring and quick fix functionality.

Dr. Carl Alphonce initiated the Green project at the University at Buffalo, SUNY, in the summer of 2004, with funds generously provided by IBM in the form of an Eclipse Innovation Grant.