Re: Status of UML 2.0



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From: Andy Evans (andye@cs.york.ac.uk)
Date: Thu 24 Oct 2002 - 18:15:38 BST


RE: Status of UML 2.0Robert,

It is probably not a sensible idea to make judgements on something
you have not read. Read it, and then comment!

Thanks,

Andy

  ----- Original Message ----- 
  From: Bauer, Robert 
  To: 'puml-list@cs.york.ac.uk' 
  Sent: Thursday, October 24, 2002 5:26 PM
  Subject: RE: Status of UML 2.0


  Heinrich, 

  Although I don't read German well, I was able to look at the web pages you referenced below.  One thing bothers me.  As I looked at the www.2uworks.org website I noticed the goal of being "unambiguous" uml.  This does not seem to be possible unless uml was no more expressive than a finite automata - that is, one could represent uml using regular expression (or equivalently a left/right linear grammar).  Now, I haven't thought about this very long or deeply, but it seems to me that while it is relatively easy to check whether two uml "graphs" are equivalent at the syntactical level, is intractable at best and quite possibly impossible - if we were to use 1st order logic to express the semantics, well at best it is only semi-deciable whether two 1st order expressions are equivalent.  Since, ocl cannot yet express all of the meta-model, it cannot possibly express the semantics of every uml model, so while one may be able to decide whether two ocl expression are equivalent (though I suspect even though ocl is not a 1st order logic, it is still undecidable due to the presence of "allInstances"), the "rest" of the semantics of the uml model are either in a natural language (clearly impossible to determine in general whether two sentences are equivalent or equivalently whether a sentence is ambiguous) or anything more expressive than a F.A. (also except for discrete context free languages, clearly impossible to determine equivalence, ambiguity, etc.).

  So, for those reasons, I am not sure why the goal is stated as it is. 

  robert 

  -----Original Message----- 
  From: Heinrich Hussmann [mailto:Heinrich.Hussmann@inf.tu-dresden.de] 
  Sent: Thursday, October 24, 2002 8:14 AM 
  To: puml-list@cs.york.ac.uk 
  Subject: Re: Status of UML 2.0 



  Hallo Hubert 

  Schau Dir mal folgende Seiten an: 
  www.u2-partners.org 
  www.2uworks.org 

  Steve Cook hat auf der UML 2002 eine private Schaetzung gesagt (nicht 
  oeffentlich), wann er erwartet, dass UML 2.0 ein Standard wird: Mitte 
  2004 fruehestens. 

  Viele Gruesse 
  Heinrich 

  Hubert Baumeister wrote: 
  > 
  > Hi, 
  > 
  > could someone please summarize the status of UML 2.0? Are there still different proposal from 
  > several partners or is there by now a common proposal? How far is UML 2.0 from being a standard? 
  > 
  > I find it a very bad decision that the UML 2.0 RFP pages on the OMG web-site 
  > (http://www.omg.org/uml/) are restricted to OMG members only. These pages, if I remember correctly, 
  > contained the most recent submissions to the RFPs and allowed to judge the status of the OMG process. 
  > 
  > Greetings, 
  >         Hubert 
  > 
  > -- 
  > Dr. Hubert Baumeister, Institut für Informatik, Universität München 
  > mailto:baumeist@informatik.uni-muenchen.de 
  > http://www.informatik.uni-muenchen.de/~baumeist 
  > phone (x49-89)2180-9375  * fax -9175 
  > 
  > To remove yourself from this list please mail puml-list-request@cs.york.ac.uk 
  > with a message containing the word "unsubscribe". 

  -- 
  Prof. Dr. Heinrich Hussmann 

  Dresden University of Technology 
  Department of Computer Science 

  Phone +49 351 463 38464   (until end of February 2003) 
  Fax +49 351 463 38459     (until end of February 2003) 
  Email Heinrich.Hussmann@inf.tu-dresden.de 
  or    Heinrich.Hussmann@informatik.uni-muenchen.de 

  Please note: I will move to University of Munich by March 1, 2003. 




  To remove yourself from this list please mail puml-list-request@cs.york.ac.uk 
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