Way back when I was an undergrad I had a professor who was a stickler for experimental method. She was also, however, always anxious to see what you had learned. As soon as she understood your experimental setup -- which was usually before the end of your explanation of it -- she'd insistently ask, "What were your results?" Between her enthusiasm for the question and her eastern-European native tongue the last word would always come out as "RHEE-zults". That question, and her unique pronunciation, have stuck in my head ever since...

Last June we did a first "experiment in openness" with the Tiger Snapshots. We posted each weekly Tiger build, in binary form, from the Beta 2 release right up to the Release Candidate. The results were positive: About ten thousand brave souls downloaded the builds and filed several dozen bugs, and the most critical handful of those bugs was fixed in time for the RC build.

Inspired by the success of the Tiger snapshots, today we posted the first of the Mustang Snapshots. We've made some significant changes this time around:

• We've started earlier. You can get build twelve today. Yes, that's twelve as in 12. There aren't a whole lot of changes in this build, mainly just bug fixes and a few small enhancements here and there, but you'll see more change going forward as new features are integrated.

  As usual, snapshot builds are not for the timid. They receive only limited testing -- just a few hours' worth to make sure that they're warm and breathing. If you want stability then you'd best wait for the Mustang beta release, but if you enjoy living on the bleeding edge then these builds are for you.

• We're shipping source bundles. For the first time ever we're shipping source bundles for a J2SE release while it's under active development (gulp). This should make it easier for interested developers to contribute to the release as it evolves. In past releases the only ways to do that were to be lucky and know someone at Sun, or be lucky and have your suggestion survive the labyrinthine gauntlet of the bug-submission process.

  Posting source bundles will also make it easier for us to be embarrassed by our mistakes, but we're quite happy to be arbitrarily embarrassed in exchange for higher quality.

• We're using java.net. One of the big goals here is to engage better with the developer community, and java.net provides excellent infrastructure for that. The bundles are being hosted in the overall j2se project, which will shortly acquire the other usual project accoutrements such as mailing lists and forums. We're also working on a streamlined process for patch submission so that you can send code directly to real live JDK engineers rather than paste it into a bug report, cross your fingers, and hope for the best.

• We're using a new license. The source bundles are covered by the Java Research License. The JRL is, to my non-lawyerly brain, a big improvement over the old SCSL license -- for one thing, I can understand it! The JRL also gives developers and researchers more flexibility than SCSL did, though it's still not an actual open source license in OSI terms (sorry).

Taken together these changes obviously entail a much bigger, and longer, experiment than the Tiger Snapshots. We certainly don't want to wait until the end to learn from the experience and make adjustments. If you have ideas on how we could do any of this better, please let us know!