Tapestry 5 Building Web Applications is an introduction to Java Web Application development using the Apache Tapestry Framework.
Besides Tapestry, software tools you will come across in this book are "db4o", "Maven", "NetBeans IDE" and "Eclipse IDE".
The second appendix, "Creating a Real Data Source with db4o", introduces db4o and gives a nice insight into enhancing the mock Web Application by doing away with the Java class way of storing and retrieving data.
http://amitksaha.blogspot.com/2008/02/tapestry-5-building-web-applications.html