Associations for association class

[jasonab]

I'm not sure if this is my problem or EA's. If I add an association class to a UML diagram, I get the link between the two classes, and the assoc class hanging off of the relationship.

I expect the two main classes to point to the assoc class, and the assoc class to point to the other two classes. Instead, the assoc class has no relationships, and the two main classes still point to each other. Code gen gives the same result.

I don't think this is correct behavior. Can anyone clarify? This is using 4.51.749

[sargasso]

See UML 2.0 superstructure page 119.

bruce

[jasonab]

See UML 2.0 superstructure page 119.

I'm afraid that doesn't tell me anything. You're referring to the section labelled Association Rules?

I don't suppose you could translate?

[KP]

I think Bruce was referring to the following, which describes how an association class is shown...

Notation

An association class is shown as a class symbol attached to the association path by a dashed line. The association path and the association class symbol represent the same underlying model element, which has a single name. The name may be placed on the path, in the class symbol, or on both, but they must be the same name.

Logically, the association class and the association are the same semantic entity; however, they are graphically distinct. The association class symbol can be dragged away from the line, but the dashed line must remain attached to both the path and the class symbol.

[sargasso]

Yep, sorry I grabbed it quickly from a paper copy on my desk.  The  section is "7.16.1 AssociationClass (from AssociationClasses)"

bruce
p.s.  Jason, I cant find a section labelled Association Rules (or AssociationRule)?

[jasonab]

Thanks for the replies, I think I was looking at the wrong spec.

Still, I'm not sure that answers my question. I know an assoc class describes the attributes of an association, but isn't it written as a many association from each class to the assoc class, and a one association from the assoc class to each of the joining classes?

[thomaskilian]

...but isn't it written as a many association from each class to the assoc class, and a one association from the assoc class to each of the joining classes?

No. Just read the definition above. Of course you can draw it in the way you described it (and likely it will behave like an association class) but the construct has been defined to be shown the way it is.

[jasonab]

Ok, I see where I didn't come across correctly.

I understand that's how it should look (dotted line and all that) - I'm used to that. When I do a codegen on the class, though, my understanding is the code should have relationships inside that association class. For that matter, if I look at the Links page of the assoc class, my understanding is it should list the two classes on either side of the relationship.

That doesn't happen. Should EA do this automatically, or should I do it manually, or is it correct with the class not actually having those relationships?

[dserodio]

I'm having problems with association classes too, maybe they're related:

I have a diagram for a package, "core", with an association class between C and I, where C is a class and I an interface.

Then I have another diagram for another package, where I import C(which shows up as core::C), and I have a class D, which realizes I(which appears as a "lollipop" protruding from D).

The problem is: I want the Association Class to show links between C and I. How can I do that?