Re: [seam-dev] Interceptor packaging convention
On 19 Apr 2010, at 17:03, Dan Allen wrote:
On Mon, Apr 19, 2010 at 11:50 AM, Pete Muir <pmuir(a)redhat.com>
wrote:
Ok. I *think* I might get what you are talking about now - you are concerned because the
interceptor has to go into the impl/ jar, not the API jar? And that therefore developers
are going to forget that it is actually part of the public API? Or?
Because otherwise, I don't have a clue how putting something in this special
intercept package can magically stop people refactoring... If I have
org.jboss.seam.intercept.ConversationBoundaryInterceptor
and someone renames it to
org.jboss.seam.intercept.ConversationEdgeInterceptor
it's just as broken for users...
That's a great point and now I see this so clearly. Interceptors must be considered
part of the public API and a stable API is expected not to shift (for backwards
compatibility reasons). It's public API because the develop must refer to the
interceptors in beans.xml (according to spec, putting workarounds aside).
Yup, it's definitely part of the API! IMO it's better to ensure this properly via
tests (e.g. we could add a tool like sigtest to our QA process, and verify all signature
changes as part of a release).
What I didn't get about the original discussion was that somehow putting interceptors
into a specific package somehow protects them from being changed - these are really
orthogonal concerns - not breaking an API and what package stuff goes in.
If there is a refactoring, it must preserve backwards compatibility through delegation
(Seam 2 did this to prevent similar breakage in configuration files).
So I guess the real issue at hand is...the consistent packaging of interceptors is really
about making the <interceptors> element as simple as possible by making all the
interceptors classes have the same number of package segments. That need may or may not be
contrived. I haven't stood in the shoes of the developer yet being required to list
out a bunch of interceptor classes.
It sounds contrived to me. Where does it come from? Given that a user might declare some
interceptors, where does that leave them?