Re: [service-orientated-architecture] Re: What is a "well defined interface"?

[Keith Harrison-Broninski]

This whole chain of thought assumes that the "semantics" of a task are somehow separate from its "execution" - that nouns are not in any way associated with corresponding verbs, if you like.  How often is this true? Books are for writing and reading, not eating or driving.  Pizzas are for making and eating, not filing or harvesting.  Flowers are for growing and picking, not drinking or automating. What I am suggesting is that "semantic decoupling" may be something of an oxymoron.  Unfortunately, it is a pervasive one - as evinced by the massive effort by academics and the BPM industry to define "process" as unrelated to the data it operates upon.  To properly understand and support business processes, you need better semantics than this - and when it comes to service interfaces, the same principles applies. The recent debate in this group about service semantics is going in the right direction, but attempting to separate interface from semantics is not a useful approach, imho.  Not only is it probably unachievable (as Ron says), but even if you managed to create a few such services, they'd be of such limited application that they'd be no use in the real world - only as the classic "textbook examples" that do nothing but mislead the reader. -- All the best Keith http://keith.harrison-broninski.info Jan Algermissen wrote: On Feb 25, 2006, at 8:15 PM, Ron Schmelzer wrote: So, can you ever truly be "decoupled"? IMHO, true decoupling is reached when the only semantics the consumer needs to know to use a given service are those that it takes to understand the task in general (regardless of which service). IOW, in order to order a pizza you need to understand the basics of ordering and what it is that you want to order (pizza). This knowledge, a uniform API and the ability of the service to show the path through the application at runtime should be sufficient to substitute the service by any other. Ah - you also need a way for the service to tell the client that it's expectation (order pizza) cannot be met (should that be the case). Jan SPONSORED LINKS Computer software Computer aided design software Computer job Soa Service-oriented architecture YAHOO! GROUPS LINKS  Visit your group "service-orientated-architecture" on the web.    To unsubscribe from this group, send an email to:  [EMAIL PROTECTED]    Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service.