SysML 1.0 FTF Avatar
  1. OMG Issue

SYSML — SysML:Usiing a BDD for Activities

  • Key: SYSML-110
  • Legacy Issue Number: 10447
  • Status: closed  
  • Source: Change Vision ( Michael Chonoles)
  • Summary:

    The SysML spec says that a BDD can be used for functional decomposition because an Activity is a Class in UML. (see the end of 11.1;

    However, the spec says elsewhere that a BDD can only be for Blocks, Packages, or constraint blocks.

    For example, Annex A.1 (p 167)

    The following are the designated model elements

    associated with the different diagram kinds.

    • activity diagram - activity

    • block definition diagram - block, package, or constraint block

    • internal block diagram - block or constraint block

    From 8.3.2, it is clear that while a block is a class, a class is not a block.

    From this, it is unclear how a block diagram can really (formally) be for an activity.

    Possible solutions

    1) Let a bdd for any classifier

    This has the extra advantage of allowing bdd’s for actors, ports, etc.

    2) Change the annex to allow a bdd to be for activities (and perhaps actors, ports…)

    3) Change the definition of a SysML activity to be both a UML4SysML Activity and a SysML Block (probably too complicated)

    Also the example diagrams (such as figure 11.1 and the figure in Table 11.3 row 1) should have a complete diagram header. This should at least include the model element type for the diagram (to be consistent with the solution above).

    They should also have a «diagramUsage» if one is required (as implied by Table 11.3)

  • Reported: SysML 1.0b1 — Thu, 9 Nov 2006 05:00 GMT
  • Disposition: Resolved — SysML 1.0
  • Disposition Summary:

    No Data Available

  • Updated: Fri, 6 Mar 2015 20:58 GMT