https://blueprints.dev.java.net/petstore/index.html
The Java Pet Store 2.0 Reference Application is a sample application brought to you by the Java BluePrints program at Sun Microsystems. This application is designed to illustrate how the Java EE 5 Platform can be used to develop an AJAX-enabled Web 2.0 application. The application comes with full source-code available under a BSD-style license, so you can experiment with it and use it in your own applications.