Apache Geronimo consists of a kernel that provides dependency management, configuration management, lifecycle management, and repository services. A GBean is a basic building block in Geronimo that wraps a service or provides a service by itself. GBeans are grouped into configurations that start and stop as a group. These configurations are themselves GBeans that use the services of other GBeans such as the repository and so on. As a result, they provide us with a hierarchy of GBeans, using services from one another in a neatly choreographed way. In this chapter, we will look at the building blocks of Geronimo that enable it to provide the services required of a Java EE 5-compliant application server. This chapter is divided into three major sections, dealing with:
Services provided by Geronimo
Configurations and deployment
Development and deployment of GBeans