Classifiers and classes

[zyx]

Hello all,

    Again I apologize for my bad english.


    What is the difference between classifiers and classes? A class is a kind of classifier but a classifier not necessarily is a class. A classifier is a mechanism that describes behavioral and structural features, but a class don’t describes it too?

    I read that a classifier is an abstract metaclass, but a metaclass is a class whose instances are classes. It is not more correct to say a metaclass is a classifier whose instances are classifiers?

    A use case, by example, is defined by a metaclass, but a use case is not a class, a use case is classifier.

[Geert Bellekens]

I think you understood it pretty well.
There are a lot of (meta) Classifiers in UML, of which (meta) Class is one.
But a MetaClass is a class (in the metamodel) whose instances are concrete UML elements (could be a class, a use case, an attribute...)

Geert

[KP]

A classifier is a mechanism that describes behavioral and structural features, but a class don’t describes it too?

Yes, a Class is a Classifier whose features are "attributes" and "operations".

I read that a classifier is an abstract metaclass

Correct, it just means you can't create a "Classifier" element in your model, you need to be more specific in what kind of classifier, e.g. Class, DataType, Interface, ...

[sargasso]

Classes get implemented, IOW  coded. Classifiers are something of which the deities speak. No more is needed.

cheers
bruce