Re: MDA/UML/OO and SOA (was Re: [service-orientated-architecture] John on Gartner, AJAX & Assorted TLAs)

[Ashley at Metamaxim]

H. Ozawa wrote:   > Eric, however, maybe thinking of a new paradigm shift toward service > oriented programming language. Like application development shifted > from flowcharts and Cobol to UML and Java/.Net, the next shift may > offer new diagramming techniques and languages. I sure would like to > hear more about it and would like to know if there is any project that is > attempting to build it.   I don't know whether the work I have been doing is of interest in this context, but it may be. So here is a short description and references to some material.   I have had a long standing interest in behaviour modelling, and languages that support direct execution of such models. Recently I have been working with colleagues on a concept called "Protocol Modelling" that is based around the idea of composing partial behavioural descriptions using the parallel composition ideas of CSP (Tony Hoare's process algebra).   This approach leads to a programming style in which partial behavioural descriptions (which can, in theory, be built using any notation you like) are combined in the manner of "mixins", giving an expressive power that is similar to multiple inheritance.   The challenge in developing the approach has been to allow these mixins to be re-used safely across the definition of multiple behavioural entities (be they objects or processes -- we don't really distinguish between the two). The approach works well, but does lead to a radically different view of what is meant by "inheritance" and the mechanisms for achieving it. However, I think we are on the right track, as attempts to include the inheritance of behaviour into conventional inheritance schemes leads to nasty complications.   The resultant paradigm for defining executable behaviour models is as different from conventional OO as OO is different from 3GL.   The following two papers will give you some idea of what we have been doing. Both are referenced from the "News and White Papers" page of the Metamaxim website (http://www.metamaxim.com/pages/news.htm): 1. The paper "State Machines as Mixins" (see "Metamaxim article in The Journal of Object Technology" under January 2004) 2. The paper "Protocol Modelling" (see "Formal Semantics" under November 2004). The first of these is a more general motivation of the ideas -- please read this one first. The second is an attempt to put the ideas on a more formal footing.   It is too early to say whether this approach has useful application to SO (in particular, process modelling), but I suspect that it does.   Rgds Ashley __._,_.___ SPONSORED LINKS Computer software program Computer software spy Computer job Database software Discount computer software 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. __,_._,___