Consistency is something David Holberton, a J2EE developer for a large aerospace company, counts on. Today, his applications will run on consistent versions of the Java Virtual Machine (JVM). Open sourcing Java "opens up innovation, but I'm concerned about fragmentation," he said.

Holberton says he's "fairly confident" fragmentation won't happen based on Sun's efforts so far to ensure a consistent development environment. But what developers at the conference don't yet know is how Sun will accomplish this and keep Java from forking, developing different implementations and hurting the underlying idea embodied by the JavaOne name.

"I think the 'how' is going to be very important," said Andrew Smith, a systems architect at Innovative Software Engineering in Coralville, Iowa. He wants to know how Sun will preserve compatibility, how testing will handled once the code is open-sourced and what happens if a variety of distributions emerge similar to Linux.

There are no answers yet to those questions. Sun CEO Jonathan Schwartz gave Richard Green, who heads the company's software division, the go-ahead for developing a plan to open-source Java, and Green made it clear that the company doesn't want to put Java on a diverging path. With that in mind, Green stressed that Sun officials will need to devise a plan to prevent that from happening.

What Sun officials insist on, however, is that Java will be open sourced. Schwartz didn't attach any caveats to his announcement and believes open source Java will broaden usage by developers as well as create new markets for his struggling company.