HF EJB question 4 on page 426

[Li Xin]

Can someone explain why option B is correct? Since the relationship is uni-directional, how come we can go from Bar to Foo by calling b2.getFoo()?
Thanks.

[Anthony Watson]

I think that the question contains a mistake and that you shouldn't be able to call b2.getFoo() on the Bar bean because if you don't have a cmr-field-name of Foo for the Bar bean, then you should not have an abstract method getFoo() for the Bar bean.

[Maggie Leber]

I'm glad somebody elss agrees with me on this one. I'm going to report it to [e-mail], because it's still not in the official errata list.

[Christopher Arthur]

I remember this one. I agree with you, too.

[Walk Rustin]

The answer is correct. Don't let the unidirectional thing blurry your judgement. Look at the cardinality. A bar can have atmost only one foo.
After the operation, f2 is connected to b1.
If B is a wrong answer ( which is not) then b2 is still connected to some foo. What foo is that? The operation has left both f1 and b2 without any partner.
Hope it helps.
- walk rustin

[Van Nguyen]

Walker,
Can you elaborate? I currently, agree with everyone else that there is no method b2.getFoo() since it is unidirectional but would like to hear more of your arguement.
Are u saying there is a be.getFoo() which returns the comp object for Foo? If so, how do you account for the relationship being unidirectional?
-Van