What does the actionURL do? It takes you to the action processing phase of the portlet. You're doing it with a custom tag in a
JSP, but here's the same sort of thing all done in one portlet below:
Notice the lines of code:
That will print out the URL. The URL itself is pretty meaningless to you, as it's generated by the portal, but if you REALLY want to see it, you can.
The ActionURL triggers the action processing phase of a portlet, which is essentially the processAction method. This method is where session management should take place, and other tasks, like mode and state changes, can only happen in this stage. This stage occurs before the rendering phase that includes methods like doView or doEdit.
Here's a full, cbt, multimedia tutorial on the topic.
You should totally take the time to look at it. The tutorial fully explains the action processing phase of the portlet.
Enjoy!
-Cameron McKenzie