Sun Microsystems has expressed "serious doubts" about the usefulness of the latest Apache Foundation project to create an open source implementation of the Java 2 Standard Edition (J2SE).

In an interview with vnunet.com, James Gosling, Java creator and Sun vice president in charge of the programming language, explained that he did not understand why the open source consortium was undertaking the project.

"I would never do that," he said about Apache's Project Harmony. "There are so many more interesting things to do with my life."

The Apache Foundation announced the project earlier this month. The organisation aims to collect a group of developers and create an open source implementation of the J2SE, which is needed to run Java code on a desktop computer.

Sun requires J2SE implementations to pass rigorous testing requirements before they can call themselves Java compliant. While this ensures compatibility between the different J2SEs, it also means that the functionalities of the final product are identical to Sun's existing offering.

Sun put the detailed requirements in place to prevent "forking", a fragmentation of the language that would force software developers to certify their code for each fork.

A similar development with Linux allowed Red Hat and SuSE to become the de facto standards. Major software vendors, such as Oracle and Computer Associates, now certify their software only for these Linux distributions.

Sun welcomes contributions from outside the company to the source code, and has a Java Community Process in place to foster discussion within the developer community and encourage input on the future direction of the language.

The inability to fork Java is the only major difference between the software licence that Sun uses for Java and the GPL-like licence that the Apache Foundation will use, according to Gosling.

"[Apache] says a lot of words about why they want to do it. Exactly why is it critical to have a delta between our source licence and the source licence that they think is appropriate?" he said.

"I understand why they would like it to be different. From our point of view that would actually be more destructive than helpful. It boils down to forking: they believe that the ability to fork is an absolutely critical right."

Gosling claimed that Java developers of enterprise software support Sun in its refusal to open the source code of Java. But they are eclipsed by more vocal open source advocates.

"If we could get the enterprise software architects to be as vocal as the Slashdot crowd, it would be a really interesting discussion," he said.

Sun will not contribute to the project, Gosling said, revoking a comment that another Sun vice president made on his blog earlier.

"We hardly have the energy to work on our [J2SE implementation]. We'll be glad to get co-operative and helpful, but there is only so much energy that is free and donatable," Gosling told vnunet.com.

In response to Gosling's remarks, Geir Magnusson, an independent software developer with the Foundation, told vnunet.com that Apache does not aim to fork Java.

An open source J2SE implementation could allow the software to spread to new devices, according to Magnusson, who pointed out that Sun's J2SE only supports Solaris, Linux and Windows.

"This is about producing a J2SE implementation that can be taken and ported and used in more places," he said.

"If I am building a device that uses Java and I could get a complete J2SE implementation from Apache, then we would have a new place for Java.

"It would be nice if every Linux distribution came with Java. Java should be like a dial-tone."

Magnusson added that current J2SE providers, such as IBM, BEA and Sun, all have to build and test their own software. An open source implementation would allow them to share that work.

He is not surprised by Sun's lack of enthusiasm about his latest project, however. Magnusson has spoken with the company about Harmony and has invited it to participate. "Sun is a little sceptical that we are able to do it," he said.

Sun has provided Magnusson with a slot at the upcoming Java One conference from 27-30 June in San Francisco.

The development of the open source J2SE software is expected to take several years.