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  1. OMG Issue

DDS12 — Object State Transitions of Figure 3-5 and 3-6 should be corrected

  • Key: DDS12-39
  • Legacy Issue Number: 9521
  • Status: closed  
  • Source: THALES ( Virginie Watine)
  • Summary:

    Object State Transitions of Figure 3-5 and 3-6 should be corrected and simplified

    Summary:

    The state transition diagrams in Figure 3-5 and 3-6 are difficult to understand, and the 2nd diagram of Figure 3-5 is missing. (Instead of this 2nd diagram, the first diagram of Figure 3-6 has wrongly been duplicated here).
    Furthermore, since it is difficult to distinguish between primary and secondary Objects and their primary and secondary states, it would be nice if more intuitive names and states could be used instead.
    Finally, some of the possible conditions in which a state transition can occur are not mentioned in these state transition diagrams, which would even require for them to become more complex.

    Proposed Resolution:

    Introduce new names for the different states, and try to re-use the same set of states for each diagram. We propose not to speak about primary and secondary objects, but to speak about Cache Objects (located in a Cache) and CacheAccess objects (located in a CachAccess). Furthermore, we propose not to speak about primary and secondary states, but to speak about a READ state (with respect to incoming modifications) and a WRITE state (with respect to local modifications).
    Decouple Objects in the Cache from Objects in a CacheAccess, it makes the the the idea of what a Cache or CacheAccess represent more understandable. The Cache represents the global Object states as accepted by the System, a READ_ONLY CacheAccess represents a temporary state of a Cache, and a READ_WRITE or WRITE_ONLY CacheAccess represents the state of what the user intends the system to do in the future.
    Since a Cache then only represents the global state of the system (and not what the user intends to do), it does not have a WRITE state (it will be VOID). A READ_ONLY CacheAccess also has no WRITE state (VOID), but a WRITE_ONLY CacheAccess has no READ state (VOID). A READ_WRITE CacheAccess has both a WRITE and a READ state, and the WRITE state represents what the user has modified but not yet committed, and the READ state represent what the system has modified during its last update.

  • Reported: DDS 1.1 — Mon, 3 Apr 2006 04:00 GMT
  • Disposition: Resolved — DDS 1.2
  • Disposition Summary:

    see above

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