I'm not sure on completely arbitary.  But I do tend to use such tools
but I have two simple rules,

1) Never expose directly, always use a Facade pattern
2) Never consumer directly, always use a proxy pattern

These two simple things provide you with the ability to evolve
elements independently.

Steve


On 11/12/06, Hitoshi Ozawa <[EMAIL PROTECTED]> wrote:
>
>
>
>
>
>
> +1. Client and server should also be completely arbitrary to make the system
>  loosely coupled. Otherwise, we'll just end up with just a rewrite of the
>  old system.
>
>  H.Ozawa
>
>
>  Robin wrote:
>  > Services operations in a real world will quite always return an
>  > element that is described in XML schema notation using a complex type.
>  > If the developer uses a tool that is marshalling/unmarshalling the XML
>  > element into an object, this marshalling/unmarshalling should not
>  > tightly couple the Object model(=value object model) to the XML
>  > schema. If you do this, it means any change in any XML element will
>  > potentially break your client.
>  > 
> <http://blogs.ittoolbox.com/eai/applications/archives/the-web-services-wise-man-9598>
>  >
>  > I would strongly advise not to use this kind of
>  > marshalling/unmarshalling tool unless it is change-tolerant.
>  > For example the mapping between the XML and the Object model can be
>  > configured without changing the code.
>  > Robin
>  >
>  > --- In [email protected], Keith
>  > Harrison-Broninski <[EMAIL PROTECTED]> wrote:
>  >
>  >> You're missing Viju's point, Steve.  Of course it's easy to build
>  >> services that utilize complex objects.  Viju's question - a deep and
>  >> important one, imho - is about limitations on the client, not on the
>  >> server.  I hope Viju won't mind if I paraphrase it:
>  >>
>  >> /If a service returns a "complex object" - i.e., an object whose
>  >> properties are not all primitive - then what are the limitations on the
>  >> client?/
>  >>
>  >> Many services are produced on the assumption that the consumer uses a
>  >> code base related to that of the producer - including, for instance,
>  >> interfaces that can be used as proxies for the objects returned by the
>  >> service.  If this is true, it makes a mockery of a key part of the SOA
>  >> concept, namely the supposed independence of producer and consumer.
>  >>
>  >  But
>  >
>  >> what client technologies allow you to call services from anywhere,
>  >> without access to the producer's code base, and utilize
>  >>
>  > programmatically
>  >
>  >> the complex objects that are returned?
>  >>
>  >> I have asked exactly this question before to this group
>  >>
>  >>
>  > 
> <http://tech.groups.yahoo.com/group/service-orientated-architecture/message/2400>,
>  >
>  >
>  >> since I have been looking for solutions since 2001.  And the _only_
>  >> practical suggestion I got was from Aleksander Slominski, whose XSUL
>  >> project <http://www.extreme.indiana.edu/xgws/xsul/> includes a "Super
>  >> Dynamic Invoker" (based on WSIF, which I also used in an earlier
>  >>
>  > attempt
>  >
>  >> to deal with the problem).
>  >>
>  >> As you say, Steve, "there should be no limitations" - but there
>  >> certainly appear to be at the moment.
>  >>
>  >> --
>  >>
>  >> All the best
>  >> Keith
>  >>
>  >> http://keith.harrison-broninski.info
>  >>
>  >> Steve Jones wrote:
>  >>
>  >>
>  >>> 1) Service is a business concept
>  >>>
>  >>> So I'm assuming you are talking about WS-*.  If you can't return
>  >>> complex XML schemas from your WS-* implementation then quite frankly
>  >>> its rubbish.  There should be no limitations.
>  >>>
>  >>> Steve
>  >>>
>  >>>
>  >>>
>  >>> On 06/12/06, *darlin' Viju* <[EMAIL PROTECTED]
>  >>> <mailto:[EMAIL PROTECTED]>> wrote:
>  >>>
>  >>>     All,
>  >>>
>  >>>     Is there any limitations for the return type of a service ?
>  >>>     My understanding is the service should return only primitive types
>  >>>     and objects which has primitive types as variables. This is to
>  >>>     ensure that the service can be used across languages.
>  >>>     Is this correct or is it like there is no limitation at all?
>  >>>     Is it posible to return an xml from a service?
>  >>>
>  >>>     Thanks,
>  >>>     - d Vj
>  >>>
>  >>>
>  >>>
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