Geir Magnusson is best known as creator of Velocity, and then as the Apache Software Foundation representative to the JCP. Lately, Geir has been involved in Apache's Geronimo project that aims to implement J2EE 1.4 in an open-source fashion. Geir is also instrumental in shepherding the nascent Harmony project through the Apache incubator stage, with the goal of having a common, open-source codebase for J2SE implementations.

In a recent ServerSide.com interview, Geir describes Geronimo, and why it is really a framework for creating server applications, with J2EE 1.4 being just one "personality" of Geronimo. He describes how Geronimo compares with other Apache IOC frameworks, such as Avalon, and mentions some Geromino features beyond standard J2EE capabilities, such as a repository for dependency management, and a deployment infrastructure that can host non-J2EE servers.

Geir also talks about Harmony, the recent Apache effort to build a fully open-source implementation of J2SE. He describes the difference in engineering class libraries versus Java virtual machines, how the Java ecosystem is based on specifications, and explains the three classes of open-source licenses.

Do you agree that there is room for an open-source J2SE implementation? What do you think of Apache's Harmony and Geronimo projects?