[Bluej-discuss] Uses arrows in BlueJ class diagrams

[Michael E. Caspersen]

Michael's description of a possible solution (see below) sounds 
very good to me!

I can't wait to get this in my hands; it will make the life of my 
students a party!

A few comments:

   o What Michael calls association should be called something
     else, (e.g. uses) because ... (see next bullet).

   o Apart from specialization/generalization, there are
     two standard relations between classes: association
     and aggregation/decomposition. The latter defines a
     hierarchical relation between classes, the aggregate
     class (whole) and the component class (part).  In UML
     these relations are termed aggregation and composition
     with the latter being the strongest (if I remember
     correctly).  Filled and unfilled diamond. Association,
     on the other hand, is a dynamic relation between equal
     classes (no hierarchy).

   o Without annotations it is difficult if not impossible
     to distinguish between association and aggregation.
     If I can only have one, it should be association.

   o The naming issue could be solved by asking the user to
     supply a name (dialog box).  The name supplied buy the
     user can be used as identifier for a new private field
     variable. In principle, the name could also be used as
     role descriptor on the arrow in the diagram, but that
     is probably not a good idea.  At least it should be
     possible to switch this on and off as with the arity/
     multiplicity option.

All the best,
Michael