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  1. OMG Issue

MOF24 — Multiple classifiers for an instance in MOF and RDF as defined in ODM

  • Key: MOF24-60
  • Legacy Issue Number: 9466
  • Status: closed  
  • Source: Model Driven Solutions ( Cory Casanave)
  • Summary:

    This is a question involving ODM as well as MOF XMI and Life-cycle.

    In ODM we have RDF and OWL defined as MOF meta models, the assumption being, of course, that you can have MOF instances of RDF graphs. But can you? In RDF & OWL an instance (at any M level) can have (and frequently does have) multiple types – it is classified by more than one class. While this is perfectly legal in UML and even in the MOF meta model, I don’t think the concept is supported in XMI or the current life-cycle. So, can you actually represent RDF in MOF? If not, the ODM models are not valid – I hope I am wrong about this.

    The ability for an instance to be classified by more than one class is a major advantage of RDF and of ontology languages, the C++ heritage in MOF of an instance statically being a member of a single class puts MOF at a disadvantage in relation to these other technologies. It makes it very difficult to represent different aspects of an instance, as can be seen from the package merge complexities - which would not have been required is we had multiple classification in MOF.

    If this is actually a semantic mis-match between MOF and ODM, is may make more sense to add the capability to MOF since the MOF meta model does not preclude this capability – it is only a restriction of the MOF-PSM (XMI).

  • Reported: MOF 2.0 — Wed, 22 Mar 2006 05:00 GMT
  • Disposition: Resolved — MOF 2.4
  • Disposition Summary:

    No Data Available

  • Updated: Sun, 8 Mar 2015 15:36 GMT