Mustang has gone Beta

; Date: Wed Feb 15 2006

Tags: Java

Java SE 6 (a.k.a. "Mustang") has reached Beta status. The sharp eyed will notice the Beta is based on build 59 while the current build available as "early access" is build 71 (or thereabouts). There's a long story behind that which I can't tell other than to say the declared Beta build kept having showstopper bugs which prevented us from shipping the beta.

Details are on the ( Java SE 6 home page. There's a lot of cool stuff in Mustang.

I want to take this moment to discuss, again, ( the Mustang Regressions contest. With this contest we are asking you to check out your application and tell us of any regressions you find. What is a "regression"? The dictionary defines it as a reversion to a less perfect state, and in software quality regression means functionality which used to work and no longer does.

Obviously you guys will eventually want to migrate your applications to Java SE 6 or some future version. There's various "gating" issues that controls that decision (e.g. your appserver might take awhile to migrate to a new Java version). One issue is the answer to this question: "will Java SE 6 break my application"?

What we want to do in this contest is to tilt that answer towards "no". To do so we need your help, as I've discussed before.

We do a lot of testing in many forms. The developers write unit tests, performance tests, and regression tests. The JCK team writes compatibility tests. The SQE team writes functional tests. We run these tests all the time doing extensive testing for each build, and doing exhaustive testing for "milestone builds" such as the Beta releases.

No matter how exhaustively we test Java we miss a very important test that we cannot do. Only you can do it, because that test is to run your application, in your environment, on your data, under your workload.

With the contest we are asking you to do that testing yourself, and to tell us of any negative results. We'll do our best to fix/address the problems either in the Mustang FCS or an update release.

Source: (


Is the source code not available for the beta?

Posted by: tackline on February 15, 2006 at 09:24 AM

Yes: ( has the source download. You can also download source for the current snapshot builds at

Posted by: robogeek on February 15, 2006 at 09:33 AM

BTW, my colleague ( Madhura Dudhgaonkar explains how it came that Beta is based on a three-month-old Mustang build.

Posted by: robogeek on February 15, 2006 at 09:41 AM

That link takes me to the "Download Java Platform, Standard Edition 6 Beta". The link on that page "Download JDK 6 source via JRL", takes me to the b71 source. I'm missing the beta source.

Posted by: tackline on February 15, 2006 at 09:55 AM

Hmm.. by jove, you're right. I've sent a query to the responsible parties and we'll see what comes from it.

Posted by: robogeek on February 15, 2006 at 10:17 AM

Thank you for bringing this to our attention. It was an oversight on our part, and the responsible parties are in the process of getting the beta source bundle out there. Keep a watch on the download page.

Posted by: robogeek on February 15, 2006 at 11:30 AM

Ah, already there: beta source download page

Posted by: robogeek on February 15, 2006 at 11:37 AM


Thank you.

Posted by: tackline on February 15, 2006 at 11:51 AM

About the Author(s)

David Herron : David Herron is a writer and software engineer focusing on the wise use of technology. He is especially interested in clean energy technologies like solar power, wind power, and electric cars. David worked for nearly 30 years in Silicon Valley on software ranging from electronic mail systems, to video streaming, to the Java programming language, and has published several books on Node.js programming and electric vehicles.