[Uml-user] aggregation / composition

[Jonathan Riddell]

> Does anyone know why i cannot  compose a class that is composed of
> two other classes ??
>
> I can make Class A a composition of Class B, but when i also try to add Class
> C to the composition of Class A I get the following :
> "Incorrect use of associations".

I'll ask my university's UML keen-beans, and you may well be right, but
off the top of my head it would seem incorrect to have a class composed
of two separate classes.  A composition seems like a total relationship,
nothing else would be included.

Does anyone know for sure?

Jonathan Riddell