A Sun Microsystems' executive has criticised Apple over its failure to include Java on its popular iPhone device.

"I think it's a mistake. I think it would provide a lot more flexibility in applications being developed," for the iPhone, said Bob Brewin, Sun Distinguished Engineer and vice president for software, at the AJAXWorld conference in California.

JavaScript runs on the phone and someone will put Java on the iPhone, Brewin said. But by not having it now, iPhone users and Java developers are being short-changed, according to Brewin.

Current Java applications, such as the LimeWire media-sharing application, could be easily ported and developers could use Java to build new programs for the iPhone, he said. There also could be a lot of Java games made to work on the device, Brewin said.

He attributed Apple's stance to the company wanting developers to develop for only a small set of APIs. "Fundamentally, they don't like open systems," Brewin said.

Apple representatives could not be immediately reached for comment, but Apple president Steve Jobs has been dismissive of having Java run on the iPhone.

Brewin also said Sun's JavaFX multimedia display technology could give the benefit of rich applications to the iPhone.

The JavaFX compiler is available in an early-access release right now. Sun expects to release components of the JavaFX runtime next year, Brewin said. Binaries for the JavaFX Mobile component of the platform will be showcased next year as well.

While JavaFX will compete with technologies such as Microsoft's Silverlight and Adobe's Flash and Flex, Brewin believes JavaFX offers advantages.

"I think the biggest strength to JavaFX, sort of from a core principle, is because it is built on Java, you know it is ubiquitous," Brewin said.

"You're not ... beholden to a proprietary implementation of another vendor," Brewin said. JavaFX also offers a simpler programming model than AJAX (Asynchronous JavaScript and XML), he added.

Also, Brewin said the Java Community Process, a multi-vendor effort on making changes to the Java platform, is going through a transition because of the recent open-sourcing of Java. "When we open-sourced Java, it just changed the dynamic a bit," he said.

One example of how it has changed is contributors have to think about whether they want to offer their intellectual property to what is now an open source platform. But Brewin anticipates the continuance of the JCP. "I think the JCP will thrive," he said.

During a morning presentation, Brewin spoke of a "blue shift" and "red shift" phenomenon in computing, comparing IT to the physics concepts of blue and red shifts, in which light turns red as it becomes more distant and blue as it gets closer.

The red shift represents applications on the web, which go out worldwide and scale to millions of people. The blue shift represents computing in the enterprise, Brewin said.

Building red shift applications requires thinking about a different application space, one in which there will not just be 10,000 people using the application behind the firewall but one that could serve 10 million customers, Brewin said.