I read a lot about Request Parameters within Portlets and I know that the Spec. tells that 'A portlet must not see any parameter targeted to other portlets.' in chapter 11.1.1.
I also found an interesting discussion about a Global Registry, as the Portal were compared to Windows and the Portlets were compared to Applications running on Windows (Word, Excel, ...).
Now I want to find out what would be the best solution to create such a global registry respectively to let parameters be visible within every Portlet. The registry must be filled in advance to the specific Portlets running.
My first solution was a ThreadLocal variable that behaves like a registry. The problem is the order in which the portlets are executed. In some cases the registry is not filled with the request parameter as the porlet that it was sent to is not yet executed.
So how can I fill such a registry before all portlets are executed?
Why don't you use our Jboss Portal InterPortlet Communication API?