what 's multiple and dynamic classifications?. These are used for better reflecting the real world when you do conceptual modeling.
For an of example of multiple classification, a person having cleared
SCJP and
SCEA is a SCJP and a SCEA. This person has two titles. But there is not a title equivalent to the sum of SCJP and SCEA.
For an example of dynamic classifiation, when a SCJP clears SCEA two years after his obtainment of SCJP, he becomes a SCEA but he is no longer a SCJP.
How to implement this is another story...
With
JAVA, I see no way to do multiple classification. But dynamic classification can be mimicked by the design
pattern STATE
what 's the difference between specification and implementation diagrams?. Specification is WHAT and implementation is HOW.
can implementation diagrams can contain aggregation/compostion symbols? I see no reason stoping you from doing that. It can only make your diagrams easier to understand.
can navigabilty and aggregation/compostion drawn together?. For composition, there is no need to do that because you alway gain access of
a part via
the whole As said in Fowler's book, the difference between aggregation and association is hard to explain. So I suggest you consider using association instead of aggregation if you need to have navigability.