I think most technologies go through a standardization process, getting requests from vendors and the linke. For Portlets, the JSR that represented the agreement on the first, standard portlet API, was JSR 168. The next one will be JSR-268.
There are all sorts of JSR's out there. Just head over to sun's
Java website and search for them.
Here's a link to the JSR-168 Portlet Specification, where you can download both the JSR168 specification, and the Portlet JavaDoc as well.
This is the Final Release of this Specification, as described in Section 3.4 of the Java Community ProcessSM Program, version 2.1. If you really want to be forward thinking when it comes to portlet development, take a look at the JSR-286 Portlet Specification from Sun (as opposed to the JSR-268 specification):
JSR 286: Portlet Specification 2.0 You can even get a real intimidating list of all the JSR requests right here:
All of the JSRs Sun is Working On -Cameron McKenzie
[ March 03, 2007: Message edited by: Cameron W. McKenzie ]
[ March 03, 2007: Message edited by: Cameron W. McKenzie ]