This past weekend I put together an example of a Spring Roo-based Jersey application that can run on Google App Engine. All code in this post is derived from the example project at https://github.com/marcisme/jersey-on-gae-example. You should be able to get a project up and running by copy and pasting the snippets in this entry, or you can clone the project and follow along. This example uses Spring Roo 1.1.1, Jersey 1.5 and App Engine SDK 1.4.0. A basic understanding of the involved technologies is assumed.
As of Roo 1.1.0, addons are created with the addon command. This is slightly different than previous versions, where addons were created with a template argument to the project command. If you find documentation referencing this old style, it’s probably out of date.