CORBA 2.5 NO IDEA Avatar
  1. OMG Issue

CORBA25 — core issue: unchecked narrow

  • Key: CORBA25-10
  • Legacy Issue Number: 4159
  • Status: closed  
  • Source: UBS ( Hans Kneubuehl)
  • Summary:

    CORBA Core should state that language mappings providing a narrowing mechanism
    are also required to provide an 'unchecked narrowing'-mechanism.

    The original CORBA Messaging specification (orbos/98-05-05) specifies an
    unchecked narrow operation that has not been changed by any Messaging RTF.
    'unchecked narrowing' is not an issue of a single language mapping. Therefore,
    it would be good if this was formulated in the CORBA Core as a general
    requirement for any language mapping.

    The originally adopted CORBA Messaging specification, orbos/98-05-05, had an
    explanatory paragraph for this purpose:

    '3.3.7 Note on Asynchrony and Narrowing of Object References
    Many programming languages map IDL interfaces to programming constructs that
    support inheritance. In those language mappings (such as C++ and Java) that
    a mechanism for narrowing an Object reference of a base interface to a more
    interface, the act of narrowing may require the full type hierarchy of the
    target. In this case, the implementation of narrow must either contact an
    interface repository or the target itself to determine whether or not it is
    safe to narrow the client’s object reference. This requirement is not
    acceptable when a client is expecting only
    asynchronous communication with the target. Therefore, for the appropriate
    this specification adds an unchecked narrow operation to the IDL mappings for
    interface. This unchecked narrow always returns a stub of the requested type
    checking that the target really implements that interface. If a client narrows
    the target to an unsupported interface type, invoking the unsupported
    operations will raise the system exception CORBA::BAD_OPERATION.'

    However, the semantics of the above have obviously not made it into CORBA 2.4.

  • Reported: CORBA 2.4.1 — Fri, 19 Jan 2001 05:00 GMT
  • Disposition: Resolved — CORBA 2.5
  • Disposition Summary:

    Incorporate changes and close issue

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