Oracle recently announced the new version numbering scheme for Java Standard Edition (SE). The new release numbering scheme has been devised for upcoming Java SE releases.

“With the recent increase of security releases we have been skipping numbers and have already had to renumber releases1. To avoid confusion caused by renumbering releases, we are adopting a new numbering scheme,” Oracle said.

Oracle will implement the new version numbering scheme for all Java update releases that include both Limited Update releases and Critical Patch Updates, with change in the frequency and way in which these releases are numbered. For example, Limited Update releases will be numbered in multiples of 20. On the other hand, Critical Patch Updates will continue to use odd numbers and will be calculated by adding multiples of five to the prior Limited Update and when needed adding one to keep the resulting number odd.

“There’s become something of a convention that security update releases are odd numbers and other releases are even numbers. I’m not sure how important that is to the outside world but if two security releases happen without a release in between you need to decide if you want to break that convention. We also had a lot of confusion arise from the need to do a few unplanned releases. Leaving gaps between planned security release numbers mean there’s already a place set aside in case any unplanned release has to happen. Keeping the odd numbering convention for security release uses up more numbers. So that’s how you end up with such inscrutable jumps in numbers,” said Oracle’s Phil Race on the OpenJDK mailing list.

Oracle has introduced the new version numbering scheme in order to create predictable release numbers for future Java releases. The new version scheme will be used for JDK 5.0, JDK 6 and JDK 7.