One way to become the "ultimate" of something is to simply declare it. JetBrains, maker of the IntelliJ IDEA Java IDE, on Thursday began previewing IntelliJ IDEA Ultimate Edition, the latest version of its commercial integrated development environment for Linux, Mac OS X and Windows. The "ultimate" designation is presumably to differentiate it from the Community Edition, which is now available as open source.

The company had previously offered a free version if IntelliJ IDEA for non-commercial use, but source code was not made available until now. Both are based on the forthcoming version 9 of the IDE, formerly code-named Maia. No release date was given.

"Open source has become the mainstream, and we continue to embrace it as an exciting challenge," said JetBrains CEO Sergey Dmitriev of the move. "In brief, we're not changing direction — we're moving forward." The company positions the Community Edition, which will be available under the Apache 2.0 license, as a good choice for developers of pure Java/Groovy applications or for doing Swing development. "It has all the crown jewels ofIntelliJ IDEA, including various refactorings and code inspections, coding assistance, debugging, TestNG and JUnit testing; CVS, Subversion and Git support, as well as Ant and Maven build integration." It differs from Ultimate in too many ways to list, but if you're working with PHP, Python, Ruby or SQL, the free version won't cut it. Also, it works with CVS, Git and Subversion, but if you're using a commercial CMS, you'll need Ultimate. Luckily, JetBrains publishes a full comparison matrix.

Ultimate 9 will include lots of new framework support, including Java EE 6 with JSF 2.0, JPA 2.0, Servlets 3.0, Bean validation; Android, Google App Engine and GWT; Adobe AIR and FlexUnit; JavaScript refactorings and debugging; Tapestry/OSGi; and PHP.

Version 9 pricing was not disclosed, but buyers of IntelliJ IDEA 8.x personal (US$249) or commercial ($599) will be upgraded for free. Visit the company's Early Access Program page to download the preview version of IntelliJ IDEA 9.