Re: Methods in the NIM requirements

[Harald Tveit Alvestrand <Harald@Alvestrand.no>]

At 03:56 18.04.2000 -0400, Weiss, Walter wrote:
>I am really struggling with this thread. Here is my basic problem. In many
>of the models I have seen (including some I have worked on), a class is
>defined with a set of attributes that can be manipulated to affect
>particular changes in the system that the object is meant to model. Hence,
>the set of attributes provide an interface to the system being described. In
>contrast, traditional OO design approaches suggest that an object has a set
>of attributes that are not directly accessable except with the use of
>methods. Hence, the method is the interface to the object (and therefore the
>system). If we want to incorporate methods in the NIM requirements, then the
>methods should represent the primary interface, obviating the need for most
>attributes (except as parameter definitons for the methods).

let me suggest that methods and attributes will in many cases be duals; you 
can define one in terms of the other, and the direction doesn't matter much.

however, attributes can be a very awkward means of modelling operations; I 
find it unnatural to model, say, a "reboot" operation, which affects the 
state of many, many attributes of many components, as a change to an 
attribute, even if it is called a "reboot button".

however, I too have a problem seeing the relation between this discussion 
and the requirements document; my reading of the requirements document is 
that it requires things for which methods are needed, and no alternate text 
has been proposed so far.

end of discussion?

                  Harald

--
Harald Tveit Alvestrand, EDB Maxware, Norway
Harald.Alvestrand@edb.maxware.no