OK cool, sorry I did not know. So ContainerBase is really a facility class and youa re already doping what I was describing. BTW I dont' think specializes(Class<T extends Archive> clazz, Path basePath) should be here, what does it do to a real user, what's the use case? WarArchive war = ear.specializes(WebArchive.class, "my.war"); should raise an exception IMO as we do not specialize, we actually add a new archive inside an archive. An EAR contains a WAR, it is not a WAR. So if I sumamrize, a descriptor is a super interface of archive that describes a given configuration file like web.xml. Why separate it from the WebArchive interface exactly? Also remember that some configuration files can be at disfferent places and be multiple. For example in JPA, orm.xmls can be named as it pleases you and you can add many of them. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4257444#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...