allow use of Servlet init parameter

Sometimes it is useful to configure multiple FacesServlet instances with some common and some distinct configuration.
Currently this is not possible - ExternalContext.getInitParameter(name) only provides access to ServletContext init parameters, but not to ServletConfig init parameters.

web.xml allows <context-param>s within <web-app> but also also <init-param>s within <servlet>.
The current ExternalContext interface provides no access to Servlet init-params. It would also be problematic to expose Servlet-init-param explicitly since Portlet API would not match.

A simple solution though would be that ExternalContext.getInitParameter(name) would first consult the Servlet <init-param> and second the web-app <context-param>s.
It would then also make sense to cache the so resolved parameters on FacesContext to optimize multiple access to the same init-parameter.

This proposal most likely affects the SPEC - if accepted create a SPEC issue as well.

regards
Hanspeter

Start at the ExternalContext.getInitParameter entry point and trace how FacesContext currently resolves and stores parameters. Compare Servlet init-param and web-app context-param handling, then verify that Servlet values take precedence without breaking the Portlet API; caching behavior is also part of the proposal.