With a growing number of companies using Java-based applications to anchor Web services and service-oriented architectures, it's not surprising the big themes of the JavaOne show this week centered on open source and integration.
Sun talked about its plans to open source the core Java code and made tangible moves in that direction with the release of several Java components, including Web services technology aimed at helping Java software work with Microsoft's .Net Web services framework. Others, such as Oracle and BEA Systems, also had announcements focusing on integrating Java into broader SOA designs.
On the open source side, Sun continues to be reluctant to completely opening the core code of Java because of concerns that the popular programming language will end up forking, thus threatening its "write once, run anywhere" philosophy.
Nevertheless, Rich Green, Sun software executive vice president, used his keynote at the show to promise attendees that Sun is working on finding a way to contribute Java to the open source community.
"There are two battling forces here," said Green, a veteran Sun executive who returned to the company just weeks ago. "There is the desire to completely open this up ... the flip side is, compatibility really matters. I don't think anybody wants to see a diverging Java platform."
The Java community is already seeing some forking with two competing development environments: Eclipse, which is backed by IBM, and Sun's NetBeans development platform.
For Sun, the challenge in opening the core Java code is to do it in a way that doesn't result in fragmentation, similar to what happened to Unix as vendors fine-tuned the operating system into separate, proprietary offerings.
Still, as far as open sourcing Java, Green says: "It's not a question of whether, it's a question of how, and so we'll go do this."
At the same time, analysts say that there will be a growing battle for control of Java as its presence in enterprise data centers grows.
"There is always the political fight for control of Java between Sun, IBM, BEA, Oracle and others," says Shawn Willett, a principal analyst at Current Analysis. "In the end somebody's got to control it in order to ensure compatibility and avoid fragmentation. ... Expect more friction [as the use of Java] expands. "
In the meantime, Sun is moving the broader Java environment in an open direction. At the show last week it released Java Enterprise Edition 5, which supports a number of important Web services standards and is designed to be easier to use than its predecessor, Java 2 Enterprise Edition, Sun executives say.
In addition, Sun unveiled a new software license, the Operating System Distributor's License for Java, which does away with restrictions that had made it difficult for Linux vendors to ship two critical Java components: the Java Runtime Environment and Java Development Kit.
One Linux distributor joined Sun executives onstage to express support for this new license. "Because of substantial changes that your team has made, we can make Linux available directly to users of free software desktops," said Mark Shuttleworth, founder and CEO of Ubuntu Linux distributors Canonical.
Though Sun is clearly interested in promoting Java on the Linux platform, the most prominent Linux distribution, Red Hat, was noticeably absent from a two-hour keynote presentation that also featured speakers from Microsoft and open source vendor JBoss.
As for the time frame to open source the core Java platform, Sun executives say it may be a year and half away.
IDG News Correspondent Robert McMillan contributed to this report.