Should I use concrete Inheritance or not?

Posted by Mez on Stack Overflow See other posts from Stack Overflow or by Mez
Published on 2010-05-29T18:17:23Z Indexed on 2010/05/29 18:22 UTC
Read the original article Hit count: 319

Filed under:

inheritance

|

propel

|

duck-typing

|

concrete-inheritance

I have a project using Propel where I have three objects (potentially more in the future)

Occasion
Event extends Occasion
Gig extends Occasion

Occasion is an item that has the shared things, that will always be needed (Venue, start, end etc)

With this - I want to be able to add in extra functionality, say for example, adding "Band" objects to the Gig object, or "Flyers" to an "Event" object.

For this, I plan to create objects for these. However, without concrete inheritance, I have to have the foreign key point to the Occasion object - giving the (propel generated) functions for all of these extra bits to anything inherited from Occasion.

I could, in theory do this without a foreign constraint, and add in functions to use the Peer or Query classes to get things related to the "Gig" or similar. Whereas with concrete inheritance, I would only have these functions in the things where they are.

I think the decision here is whether I should Duck Type the objects (after all they are occasions) or whether I should just use the "Occasion" object as a "template" (only being used to search for things, like, all occasions at a venue)

Thoughts? Comments?

© Stack Overflow or respective owner

Related posts about inheritance

Single Table Inheritance (Database Inheritance design options) pros and cons and in which case it us

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi, I study about today about 2 database design inheritance approaches: 1. Single Table Inheritance 2. Class Table Inheritance In my student opinion Single Table Inheritance make database more smaller vs other approaches because she use only 1 table. But i read that the more favorite approach… >>> More
How to use Private Inheritence aka C++ in C# and Why not it is present in C#

as seen on Stack Overflow - Search for 'Stack Overflow'
I know that private inheritance is supported in C++ and only public inheritance is supported in C#. I also came across an article which says that private inheritance usually defines a HAS-A relationship and kind of an aggregation relationship between the classes. EDIT: C++ code for private inheritance: The… >>> More
[PHP] Singleton class and using inheritance

as seen on Stack Overflow - Search for 'Stack Overflow'
I have am working on a web application that makes use of helper classes. These classes hold functions to various operation such as form handling. Sometimes I need these classes at more than one spot in my application, The way I do it now is to make a new Object. I can't pass the variable, this will… >>> More
Difference between Inheritance and Composition

as seen on Stack Overflow - Search for 'Stack Overflow'
Are Composition and Inheritance are the same? If I want to implement the composition pattern, how can I do that in Java? >>> More
C# Interface Inheritance (Basics)

as seen on Stack Overflow - Search for 'Stack Overflow'
Why does the following produce a compiler error: public interface OwnSession : ISession { } [...] OwnSession s = SessionFactory.OpenSession(); // compiler error (in german unfortunately) [...] "SessionFactory" returns a "ISession" on "OpenSession()" (NHibernate) >>> More

Related posts about propel

Using Propel ORM in my own custom classes

as seen on Stack Overflow - Search for 'Stack Overflow'
I am refactoring a few classes I wrote a while ago, into my Symfony project (v1.3.2 with Propel ORM). The classes originally used direct connections to the database, I want to refactor those classes (stored in $(SF_LIB_DIR)) so that I can call propel and also use the ORM objects. To clarify, So… >>> More
Should I choose Doctrine 2 or Propel 1.5/1.6, and why?

as seen on Programmers - Search for 'Programmers'
I'd like to hear from those who have used Doctrine 2 (or later) and Propel 1.5 (or later). Most comparisons between these two object relational mappers are based on old versions -- Doctrine 1 versus Propel 1.3/1.4, and both ORMs went through significant redesigns in their recent revisions. For example… >>> More
Propel Single Table Inheritance Issue

as seen on Stack Overflow - Search for 'Stack Overflow'
I have a table called "talk", which is defined as abstract in my schema.xml file. It generates 4 objects (1 per classkey): Comment, Rating, Review, Checkin It also generates TalkPeer, but I couldn't get it to generate the other 4 peers (CommentPeer, RatingPeer, ReviewPeer, CheckinPeer), so I created… >>> More
Zend Framework :: ORM - doctrine / propel over Zend_Db_Table

as seen on Stack Overflow - Search for 'Stack Overflow'
Hi guys, do anyone suggest using an external ORM like Doctrine/Propel over the defualt Zend_Db_Table in Zend Framework ? I think your answers with reasons would be valuable across the ZF community. -DevD >>> More
Zend_Form Creation for Propel Objects

as seen on Stack Overflow - Search for 'Stack Overflow'
I'm currently working on a project where I use Zend Framework with Propel. I'm looking for something that'll create Zend_Forms for Propel objects, preferably in a similar way to django's modelforms Is there anything out there that does this already, and if not, what would be the best way to go about… >>> More