Re: Auto selection

Responding to Kazakov...

Note that in event-based interfaces there is no need to send data by reference. That's because there is no return when an event is generated since there could be an arbitrary delay between when an event is generated and when it is consumed by the receiver in asynchronous communications (e.g., distributed). Thus any values returned by the receiver are sent back in a separate event data packet where the sender/receiver roles are reversed.


No. It is because both parties either exactly know or don't care about the
states of each other. This is the source of all problems events have.

Asynchronous nature of events is not an advantage. It is a premise. When
states become too complex to reconstruction on the peers, the architecture
collapses.

Asynchronous communication is the most general representation of communication. Synchronous communications are just a special case of an asynchronous description where the message order is deterministic. That's why in OOA/D messages are separated from methods and all behavior communications are assumed to be asynchronous. One can always implement an asynchronous model in an environment that is inherently synchronous without change. But one cannot always implement a synchronous model in an inherently asynchronous environment without modification.

At a more philosophical level, the separation of message and method ensures decoupling because the message sender does not need to know anything about who the receiver is and what the message receiver does in response. So the message sender can't depend on what the message receiver does. That elimination of hierarchical dependencies is the main benefit of OO development.


*************
There is nothing wrong with me that could
not be cured by a capful of Drano.

H. S. Lahman
hsl@xxxxxxxxxxxxxxxxx
Pathfinder Solutions
http://www.pathfindermda.com
blog: http://pathfinderpeople.blogs.com/hslahman
"Model-Based Translation: The Next Step in Agile Development". Email
info@xxxxxxxxxxxxxxxxx for your copy.
Pathfinder is hiring: http://www.pathfindermda.com/about_us/careers_pos3.php.
(888)OOA-PATH



.

Relevant Pages

  • Re: Messages as first class objects
    ... Responding to Gagné... ... "ChasingYou" to "I'mMOvingOut" separately from either the message sender ... or the message receiver. ... these are three separate design activities focused on three different ...
    (comp.object)
  • Re: Configuring TCPIP SMTP server to ignore undeliverable mail??
    ... > The only addres it could validate is the postmaster because it is on the same ... > username on a different node in the intranet. ... > would allow the receiver to perform destination validation right away. ... responses wait 30 seconds or so before responding. ...
    (comp.os.vms)
  • Re: UML Question (Object <-> ObjectFinder?)
    ... > Responding to Parker... ... >> be handled by the receiver. ... > I am arguing the 1:1 mapping is not sufficient in some cases. ...
    (comp.object)
  • Re: BYU Prof. Reveals WTC Demolition Truth
    ... "I don't know to whom you are responding (it's generally considered ... For some reason the Google posting editor didn't quote you as ... people's communications with an eye to a lot of the unspoken (or ... if he has some theory it is probable that there is some strong support ...
    (sci.physics.fusion)