I've seen what I think was this at work in a WebSphere descriptor...
The idea is that you can unambigously identify any element in the
standard dd, by adding an 'ID="xxx"' attribute, then in your proprietary
dd you can add further information about that element and use the ID to
unify the two descriptions.
Some things in the standard dd already have unique names (servlets
etc..), some things may not and thus the vendor might need recourse to
Jetty, AFAIK, does not make use of this,
>I am working on a deployment plugin for JBoss IDE and had a question about
>the servlet spec (I was reading 2.3). On pages 112-116 it describes an ID
>mechanism so that tools can provide additional deployment information. I
>don't really understand what it is talking about. Does anyone have an
>example of how these are used? Do Jetty and Tomcat have different
>non-standard depoyment information?
>Here is a portion of the spec I was referencing. It is several pages so I
>have just reprinted the beginning:
>The ID mechanism is to allow tools that produce additional deployment
>information (i.e., information beyond the standard deployment
>descriptor information) to store the non-standard information in a
>separate file, and easily refer from these tool-specific files to the
>information in the standard deployment descriptor.
>Tools are not allowed to add the non-standard information into the
>standard deployment descriptor.
><!ATTLIST auth-constraint id ID #IMPLIED>
><!ATTLIST auth-method id ID #IMPLIED>
><!ATTLIST context-param id ID #IMPLIED>
><!ATTLIST description id ID #IMPLIED>
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