DDS-PSM-Cxx 1.0 FTF Avatar
  1. OMG Issue

DDSPSMCF2 — Useless ReaderQuery on DataReader read/take

  • Key: DDSPSMCF2-3
  • Legacy Issue Number: 17066
  • Status: closed  
  • Source: ZettaScale Technology ( Angelo Corsaro, PhD.)
  • Summary:

    The ReaderQuery class bundles together the read-state as well as potential read conditions. However the read-condition is not always present. This leads to code that needs to check all the time wether something is set or not, which is not only very elegant/efficient but it is also error prone

    Remove the ReaderQuery and let the read API deal, through proper operations overloads, with ReadState and potential ReadConditions. This way it will always be clear if a read/take is with a condition or not both for the client code and the DDS implementor.

  • Reported: DDS-PSM-Cxx 1.0b2 — Thu, 26 Jan 2012 05:00 GMT
  • Disposition: Resolved — DDS-PSM-Cxx 1.0
  • Disposition Summary:

    The DataReader API has been updated to provide the proper read/take overloads and remove the useless ReaderQuery. The concept of a Selector has been introduced to orchestrate complex read/take operations requiring selection based on state, content and instance. The new API is orthogonal, simple and composable. Below an example usage of the selector API:

    LoanedSamples<Foo> ls =
    . content(query)

    This example takes the samples matching the query q for the instance with given handle.

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