EJB implementation of Geronimo RENEGADE:OPENEJB and Apache Geronimo

What's so great about Enterprise JavaBeans (EJBs), and why is it so important to java™2 Platform, Enterprise Edition (Java ee) development? In this issue of the Geronimo rebel column, OPENEJB co-founder David Blevins will describe what EJB can do for you and explain how OPENEJB is chosen as an EJB implementation of Apache Geronimo.

Brief introduction

To be honest, in my opinion, EJB is not easy to use. They require developers to devote more energy to their applications than they think; their underlying interfaces force you to implement many features that you don't even need, and because you need to run them in a container, it's tricky to use JUnit to test them with the rest of your application.

However, they may be precisely the cornerstone of the development of Java EE.

So when the powers that was invited me to choose OPENEJB as an EJB implementation of Apache Geronimo in this phase of Geronimo Renegade, my interest was stimulated. Maybe I can finally figure out what's so great about it.

How OPENEJB becomes part of the Apache Geronimo

I called David Blevins, who created the OPENEJB with Richard Monson-haefel six years ago, and he created Geronimo. I want to know what OPENEJB provides for Geronimo, and what the EJB itself provides for developers.

I asked him first how OPENEJB was raised in larger projects such as Geronimo. David explained that he had already supported the Geronimo project when Geronimo was not officially released and was just a rumor. "So I'm definitely part of what's called a Geronimo conspiracy," he jokingly said.

Ah, another conspiracy. I asked him why he used to describe Geronimo like that. "Oh, Geronimo is really very FUD (fear, uncertainty, suspicion), for those of us who are so advertised." He explained that the goal of the Geronimo founders was first to assemble the right people before considering the right components. "The individuals involved in creating Geronimo basically put themselves and their code aside and decided to put themselves into the project first," David told me. Basically, they start by trying to create a project from a whiteboard.

So how did OPENEJB become part of this whiteboard? "Oh, I guess the reason is what you know," David said. But he is not very serious. In fact, at first Dain Sundstrom, one of the founders of the original Geronimo, invited him to join the project. Dain actually tried to hire David for a similar open-source project a year ago: "For a while he took part in every social gathering Twin cities Java Users Group (Tcjug) and kept pestering me about it." ”

When they did come together, it was meant to be. Although they both came from Minnesota, David was teaching San Francisco when the Geronimo project was formed. "I said, ' That's it, I'm in San Francisco now, so you have to wait until I return to Minnesota." ' Of course he said, ' Well, I'm also in San Francisco ', and he just returned from a meeting. So we got together in San Francisco that day, and he thought he'd continue to get the no I gave him. But when the center of gravity moves from another project to the Apache Java EE implementation, the answer immediately becomes yes. ”。

And, as OPENEJB's leader (because Monson-haefel had left a few years ago), David was determined to revive the community around Geronimo's work. "We only know that this is the right thing to do," he said.

Not only that, the two groups OPENEJB and Geronimo have established rare collaborations in large projects. OPENEJB's Alan Cabrera wrote the Geronimo security system. Aaron Mulder, the author of a freely downloadable book about Geronimo, also solemnly examined the console donated by IBM®. The Dain Sundstrom and David jencks of Geronimo have done countless work for OPENEJB to follow the EJB 2.1 (the Open EJB originally followed EJB 1.1). Gianny D ' Amour,geronimo's early additions, fully promoting what David called "the largest Geronimo or OPENEJB patch I've ever seen, basically finished our CMP (container-managed persistence, Container management persistence) implementation. Jacek Laskowski, a longtime contributor to OPENEJB, first started Geronimo-tomcat integration work, which was driven by Geronimo Jeff Genender, and Jeff Genender eventually became Open The contributor to the EJB.