JBoss is an open-source J2EE-based application server that is rapidly increasing in popularity. News.com has an interview with Marc Fleury, President, JBoss Group. A few quotes by Marc:
What we need to do is for the decision makers higher up to be more comfortable with an open-source approach. I think right now open source, in general, suffers from a perception problem. The perception is that open source is not supported.
What I like about [Microsoft .Net] and really try to emulate–and that’s a departure from the J2EE vision–we want to bring the services of transaction, security, persistence, etc., in an orthogonal fashion to objects. What that really means is for a developer to leverage these operating system services, instead of having to learn J2EE, they just write simple Java objects, like in .Net. Just a straight object they already know how to write. And they give an XML file that says, “System, provide this service for my object.” It’s a much simpler way to program, and a much more intuitive way to program because it is true that J2EE has gotten bloated.
Instead of learning additional APIs and interfaces that make you reprogram applications, you want to take existing applications and just configure the server to work with existing objects. It’s a simple technical point.