The code mostly speaks for itself, so if you are interested in how to extend Groovy-Eclipse, first read part I of this article, and then download the example project.
Here is the example plugin project that extends Groovy-Eclipse. Import this plugin into your Eclipse development workspace.
And here is a simple runtime project that uses all of the extensions provided in the plugin project. Import this project into your Eclipse runtime workspace. If you want to create your own project that uses this example, be sure to add the following project nature to your .project file:
Once again, the code speaks for itself, so there is nothing more that I need to say about it. Enjoy!