Author Topic: Sense of UML  (Read 7683 times)

jeshaw2

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Re: Sense of UML
« Reply #15 on: October 13, 2005, 05:49:11 pm »
Quote
Quote this and you'll see
???

[SNIP] !
I think I got it  :)  I was looking for a meta-tag button for this. 8)

Thanks
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thomaskilian

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Re: Sense of UML
« Reply #16 on: October 14, 2005, 12:20:39 am »
You should have used the quote button on top of my post not the button from "Add YABB tags". That would have cited everything including the metatags for SNIP. However, you managed it without :)

mikewhit

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Re: Sense of UML
« Reply #17 on: October 14, 2005, 04:52:06 am »
As regards the dead account holder, in terms of the model, perhaps the missing detail was "reasons for closing account (#27) - death of account holder / action - reconcile account credit balance with estate as of date of death, cancel any charges accruing after date of death."

... since as far as the system goes, you should just be modelling the lifecycle of the account, not (ahem) the lifecycle of the account-holder.
« Last Edit: October 14, 2005, 04:53:38 am by mikewhit »

Paolo F Cantoni

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Re: Sense of UML
« Reply #18 on: October 14, 2005, 05:13:23 am »
Quote
As regards the dead account holder, in terms of the model, perhaps the missing detail was "reasons for closing account (#27) - death of account holder / action - reconcile account credit balance with estate as of date of death, cancel any charges accruing after date of death."

... since as far as the system goes, you should just be modelling the lifecycle of the account, not (ahem) the lifecycle of the account-holder.
With respect, young mike, I believe you are hoist by your own petard... ;)
death of account holder is modelling the holder...
I leave it as an exercise for the reader to demonstrate that in order to ensure that the system behaves consistently it is a consequential requirement that if one account held by this account holder is closed to due this reason, then all accounts held by the account holder must also be candidates for closure for the same reason.  Therefore...

Paolo
« Last Edit: October 14, 2005, 06:49:45 am by PaoloFCantoni »
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... Therefore, aim for consistency; in the expectation of achieving correctness....
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mikewhit

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Re: Sense of UML
« Reply #19 on: October 14, 2005, 06:13:10 am »
Well, it's just an event (with all due respect to the deceased ...)

Paolo F Cantoni

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Re: Sense of UML
« Reply #20 on: October 14, 2005, 06:48:40 am »
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Well, it's just an event (with all due respect to the deceased ...)
Yes, but it's not a disembodied event (pun intended) ;D
The event is the fact of the account holder's death.   How do you manage the other accounts without the account holder and their death?

Paolo
« Last Edit: October 14, 2005, 06:50:42 am by PaoloFCantoni »
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jeshaw2

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Re: Sense of UML
« Reply #21 on: October 14, 2005, 07:17:27 am »
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[SNIP]The event is the fact of the account holder's death.   How do you manage the other accounts without the account holder and their death? [SNIP]
Perhaps we have joint ownership or a transfer of the account's ownership?  ;D  

I suggest the model was missing an Inheritance feature?  :-/
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Paolo F Cantoni

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Re: Sense of UML
« Reply #22 on: October 14, 2005, 07:28:48 am »
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Perhaps we have joint ownership or a transfer of the account's ownership?  ;D  

I suggest the model was missing an Inheritance feature?  :-/
That doesn't alter the fact that all the accounts for which this person is an account holder are candidates for closure.  They have to be examined and a decision reached.

My point is, to do the job properly, the system needs to understand there is an account holder (who may be a person) who may die and when they die, all their accounts need to be checked in case they need to be closed because the account holder died.

Paolo
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jeshaw2

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Re: Sense of UML
« Reply #23 on: October 14, 2005, 01:23:56 pm »
Agreed  :)
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KP

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Re: Sense of UML
« Reply #24 on: October 16, 2005, 04:21:04 pm »
Well I agree with Mike and Paolo... It is the responsibility of the Account object to deal with a death of account holder event; it is the responsibility of the AccountHolder object to pass death of account holder events on to each Account object; and it is the responsibility of the Requirements Analyst to remember to put the possibility of such events in the spec in the first place!
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jeshaw2

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Re: Sense of UML
« Reply #25 on: October 16, 2005, 04:51:53 pm »
Agreed, but a common oversight.  The Requirements Analyst probably spent too much time as a Java developer.  No need for destructor methods there.  ;)  I'm bothered that the Quality Team didn't catch that either.
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Paolo F Cantoni

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Re: Sense of UML
« Reply #26 on: October 16, 2005, 05:11:47 pm »
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Well I agree with Mike and Paolo... It is the responsibility of the Account object to deal with a death of account holder event; it is the responsibility of the Account Holder object to pass death of account holder events on to each Account object; and it is the responsibility of the Requirements Analyst to remember to put the possibility of such events in the spec in the first place!
I'm actually saying more than that...  I'm saying it is the responsibility of the Person object to notify the Account Holder object that it died.  Because this person is also an Employee of the bank, person has to notify employee also.  Oh, and by the way, the person also had a housing loan...  And was the employee elected director on the board...

It's about resisting business implerialism...  The world works the way the enterprise sees it - NOT!

Paolo
« Last Edit: October 16, 2005, 05:12:14 pm by PaoloFCantoni »
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... Therefore, aim for consistency; in the expectation of achieving correctness....
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thomaskilian

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Re: Sense of UML
« Reply #27 on: October 17, 2005, 12:38:21 am »
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...it is the responsibility of the Person object to notify the Account Holder object that it died...

Halleluja

jeshaw2

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Re: Sense of UML
« Reply #28 on: October 17, 2005, 05:05:53 am »
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I'm saying it is the responsibility of the Person object to notify the Account Holder object that it died....

The world works the way the enterprise sees it - NOT!

Dead people talking to the living?  ???  My world doesn't work that way.  In such situations, the death notifications always came by way of direct observation (I killed it, I saw it happen, etc.) or from 3rd parties (Stewards, executors, friends, etc.). I think it might be the same for the death of a network connection object as a result of a loss of communication.  I suggest that the dead are not always able to speak.
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thomaskilian

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Re: Sense of UML
« Reply #29 on: October 17, 2005, 06:30:55 am »
I guess Paolo forgot that there is no one-to-one relation between model and real world. Whilst (computer-)objects can be held reponsible for being killed/about to being dead, the real world does not offer such a feature :o For me, I'm not able to find my destructor operation. Except I'll commit suicide and arrange everything in advance. Or maybe my testament should be set up accordingly ???