Question regarding a container of objects

[tomix]

Hi,

assuming i have a container of objects, for example:

Course contains a list of CourseOffer which itself is a container of
duration objects

And assuming CourseOffer only contained by Course

i wonder what do you think is a better way to implement it


Course* c=GetCourse();
CourseOffer* cf=new CourseOffer(.....);
cf->AddDuration(10,12);
cf->AddDuration(16,20);
c->Add(cf);
:
:

or

Course* c=GetCourse();
CourseOffer* cf=c.CreateCourseOffer(....);
cf->AddDuration(10,12);
cf->AddDuration(16,20);

I'll go for the second since course control the creation and lifetime
of a course offer

Thanks in advance.

 

[Victor Bazarov]

assuming i have a container of objects, for example:

Course contains a list of CourseOffer which itself is a container of
duration objects

And assuming CourseOffer only contained by Course

i wonder what do you think is a better way to implement it


Course* c=GetCourse();
CourseOffer* cf=new CourseOffer(.....);
cf->AddDuration(10,12);
cf->AddDuration(16,20);
c->Add(cf);

or

Course* c=GetCourse();
CourseOffer* cf=c.CreateCourseOffer(....);
cf->AddDuration(10,12);
cf->AddDuration(16,20);

I'll go for the second since course control the creation and lifetime
of a course offer

Thanks in advance.

If 'CourseOffer' has to be public, then yes, the latter choice is better.
But if 'CourseOffer' is just an implementation detail of 'Course', then
you could simply add the proper interface to 'Course'...

V

 

[Daniel T.]

Hi,

assuming i have a container of objects, for example:

Course contains a list of CourseOffer which itself is a container of
duration objects

And assuming CourseOffer only contained by Course

i wonder what do you think is a better way to implement it


Course* c=GetCourse();
CourseOffer* cf=new CourseOffer(.....);
cf->AddDuration(10,12);
cf->AddDuration(16,20);
c->Add(cf);
:
:

or

Course* c=GetCourse();
CourseOffer* cf=c.CreateCourseOffer(....);
cf->AddDuration(10,12);
cf->AddDuration(16,20);

I'll go for the second since course control the creation and lifetime
of a course offer

Thanks in advance.

I generally go for either completely private, or generally extensible.
This means either option one above (which allows us to provide
sub-classes of CourseOffer to a Course,) or make it so the user of
Course need know nothing at all about the CourseOffer class.