- From: <Noah_Mendelsohn@lotus.com>
- Date: Tue, 3 Apr 2001 14:40:37 -0400
- To: "Martin Gudgin" <marting@develop.com>
- Cc: "Frank DeRose" <fderose@home.com>, "Jean-Jacques Moreau" <moreau@crf.canon.fr>, xml-dist-app@w3.org
Martin Gudgin writes:
>> If schema descriptions of XMLP messages are available
>> then no specific encoding is necessary. A default encoding
>> is useful for environments that do not have schema support
>> for whatever reason. In these cases the default encoding
>> acts like an implicit schema. Personally I think the SOAP
>> encoding stuff in Section 5 of the spec is pretty reasonable
>> apart from the array stuff.
A rare case where I don't quite agree with Gudge, though I might agree
with the spirit of where he's trying to go. The SOAP V1.1 (chapter
5)encoding, in particular, describes not just the legal forms of a
message, but the interpretation of those forms in a graph model. For
example, this model can successful confer the fact that parameters 1 & 3
to some RPC don't just look the same, they are the same (or with a
different representation, that they just have the same content.)
To put it in Java terms, the difference between:
Integer one= new Integer(1);
Integer two= new Integer(2);
x = myMethod(one, two, one);
and
Integer oneA= new Integer(1);
Integer two= new Integer(2);
Integer oneB= new Integer(1);
x = myMethod(oneA, two, oneB)
A schema per se tends to capture only the legal forms of a message. I
think there are two separate issues here: (1) are you describing the just
serialized form of a message or also a richer data model that it might
represent? and (2) do you make that in the message itself and/or in some
external description such as a schema/WSDL file etc. Point (1) is the
main one I am describing; point (2) has been debated lately on the SOAP
discussion list, and tends to depend on whether you have lots of similar
messages and whether you have statically typed infrastructures that prefer
to get the descriptions ahead of the messages.
------------------------------------------------------------------------
Noah Mendelsohn Voice: 1-617-693-4036
Lotus Development Corp. Fax: 1-617-693-8676
One Rogers Street
Cambridge, MA 02142
------------------------------------------------------------------------
Received on Tuesday, 3 April 2001 14:43:14 UTC