Tapestry and HiveMind follow a different cycle, based on a major version number and a minor version number, i.e., 3.1. Major version 3, minor version 1. Major versions don't happen very often, since they represent a near-total rewrite of the framework. Minor versions change in an orderly fashion, representing incremental improvements. In general, we want to maintain backwards compatibilitily from one minor version to its predecessor, but all bets are off when the major version changes.
A change to minor version represents a new release, which has its own lifecycle (and takes several months). Releases go through stages:
- alpha - code coming together, features being added, removed, documentation nowhere, too chaotic to use for real work. Additionally, deprecated code from previous releases may be stripped out.
- beta - things setting down, the goal is to stop adding features, stabilize and document
- rc - release candidate; exposed to a wide audiance so as to find any final bugs
- GA - General Availability - the final version that people should use.
So for each release, there will be a number of incremental versions, as the code goes through these cycles. For example: 2.3, 3.0-alpha-1, 3.0-alpha-2, 3.0-beta-1, 3.0-beta-2, 3.0-beta-3, 3.0-rc-1, 3.0, 3.1-alpha-1.
It's possible, though we've avoided it so far, to "double dip"; for example, drop from beta back into alpha.
This system works well; the older numeric system (from the 1.0 and early 2.0 days of Tapestry) made it hard to tell how stable the code was, now the stability (alpha, beta, rc) is part of the name (and thus, incorporated into the distribution and even the names of the library JARs).
I adapted this naming sequence from somewhere, can't remember exactly where. I find it much more managable than a fully numeric system (quick: how stable is 220.127.116.11.1?) The code goes through known stages (we do a vote on each stage transition). I've been encouraging other projects (such as OGNL) to make use of this same naming system.