Re: More namespaces perversion

David Brownell (db@Eng.Sun.COM)
Thu, 08 Oct 1998 10:34:39 -0700


Peter Murray-Rust wrote:
>
> There have been warnings about the complexity of registries - I assume that
> the xml-ea1 props file is a registry?

What do you mean by 'registry'? Currently it's just the simplest
convention for associating XML Beans ("XObjects") with element names;
and since it's a flat namespace, it can't plug in to XML namespaces.

Sometimes when folk say "registry" they mean some global database.
I design such things out of systems every chance I get.

> Personally I don't yet care. I'd much
> rather see us try to make this work than simple wait around. I'm game for
> whatever URI<->functionality mapping we choose (as long as it's simple) so
> that we can at least get some experience.
>
> David's done it, I've done it - I assume there are others. It's part of
> XObjects and needs addressing soonest :-)

A draft I wrote up a while ago defined such bindings in XML syntax
something like this ...

<bindings>
<!-- a set of namespace-specific bindings -->
<namespace
uri="http://www.example.com/xmlbeans/app1">
codebase="xmlbeans.jar"
>
<element name="reservation">
<bean class="com.example.app1.Reservation"/>
<!-- Bean tag actually lets you define properties
and so on -->
</element>
<!-- ... more element bindings in this namespace -->
</namespace>
<!-- ... more namespace-specfiic bindings -->
</bindings>

That sketch omits two important features: (a) importing bindngs
defined for other namespaces, (b) document-specific bindings, such
as for the "default" namespace or embedded in a document.

So for example a <?bindings uri="..."?> directive might be used to
associate a preferred set of bindings with a document.

- Dave