KDM 1.4 RTF Avatar
  1. OMG Issue

KDM14 — Navigability used for code generation

  • Key: KDM14-289
  • Legacy Issue Number: 19729
  • Status: closed  
  • Source: Adaptive ( Mr. Pete Rivett)
  • Summary:

    Strictly speaking end ownership should be used for generating operators not navigability. e.g. if the property is an ownedAttribute of the class, not whether it's navigable.

  • Reported: KDM 1.3 — Sat, 21 Feb 2015 05:00 GMT
  • Disposition: Resolved — KDM 1.4
  • Disposition Summary:

    Clarify specification text regarding association end ownership

    From Pete Rivett:
    Navigability is an implementation hint that the navigation should be efficient.
    It is quite conceivable to have an ownedAttribute which is not seen an important for it to be efficient (e.g. the implementation might iterate through all instances of the target to look for a link to the source).
    Likewise there might be an end owned by association where efficiency is important but there is no ownedAttribute – especially for cross-metamodel associations (or those involving MOF Element) where it is not allowed to add an ownedAttribute to an external metamodel or MOF itself.

    Though KDM may have a pattern that always combines ownership and navigability, the specification should reference ownership.
    What I’m looking for to resolve my issue is:

    • Use ownership not navigability in the text
    • Use the dot notation in the diagrams to show end ownership

    Overview of the proposed resolution:
    Modify the specification text of section 6.2.1 Diagram format according to the suggestion by Pete. Do not use the dot notation in the diagrams, as the convention of the diagrams is fully described in section 6.2.1, the pattern is consistent, and last but not least, introducing the dot notation involves a massive change to the specification text. Instead, add text to the key semantic sections in the kdm core, emphasizing association end ownership.

  • Updated: Tue, 12 Jul 2016 14:44 GMT