Re: inherited composition

On 29 Apr 2005 06:34:31 -0700, karl.wettin@xxxxxxxxx (karl wettin)
wrote:

>Given
>
> [X]<#>----[A]<|----[B]----<#>[Y]
>
>does above imply that [B] is associated to [X] XOR [Y]?

Since you didn't put the arrowheads on the composition relationships,
things are a bit unclear. UML says that if you don't put the
arrowheads in, then the association is bi-directional. Thus, X knows
about A, and A knows about X. I don't think you really meant this. I
think you meant:

[X]<#>---->[A]<|----[B]<----<#>[Y]

In this drawing X knows about A, but A does not know about X. Y knows
about B, but B knows nothing of Y. And, of course, B knows nothing
of X.



-----
Robert C. Martin (Uncle Bob) | email: unclebob@xxxxxxxxxxxxxxxx
Object Mentor Inc. | blog: www.butunclebob.com
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but to set a limit to infinite error."
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.