[thelist] more OOD fun

[Marcus Andersson]

Steve Lewis wrote:
> Scott Dexter wrote:
> 
>> The specifics: Person is subclassed into Guest and Guide classes. The
>> Guest class extends Person by adding payment information and
>> comments, items not in the Guide class. Now in the application, if I
>> don't have teh payment information in the IPerson interface, I can't
>> get to it, unless I declare the object as a Guest, which avoids the
>> interface, which is not the best thing to do ... right?
> 
> There are more complex relationships possible.  I am going to be 
> frustrating and answer your questions with other questions.
> 
> Why do you need to get the payment information out of the (Guest) Person 
> in order to use it?  The class should be more than a data structure, 
> remember.  Does it make sense to delegate the responsibility of handling 
> payment activities to the Guest itself?
> 

+1

Check out the "code smell" Feature Envy at http://wiki.java.net/bin/view/People/SmellsToRefactorings or 
http://c2.com/cgi/wiki?FeatureEnvy (it's based on Martin Fowlers "Refactoring")

/Marcus