OO ABAP

When I started glancing thru ABAP WD, what i realized was that we need to know the concepts of OO ABAP before we understand the WD concepts...

I would like to pen down some of the Object Oriented Concepts which are not too clear at first (and also some brain teasers in interviews)...

Difference between Abstract Class and Interface:

The main difference is that no implementation of method is possible in Interface(That is actually the characteristic of interface; only when you don know the method's functionality do you go for interfaces, also when you want the class to compulsorily implement few methods ).

Abstract methods, on the other hand, may have methods implemented. But, even if one method is abstract, the class containing it will be labelled abstract. Abstract classes are destined to be inherited. They cannot be instantiated as such (Objects cannot be created of Abstract Classes).

What I was perplexed about was the narrow cast and wide cast. If some one can tel me bout the real time scenarios where you can use these concepts, I will be really grateful.

Bye for now...........

Catchin up..

Its been quite some time since my last post.. and lot of things have taken place since then. I finished my ABAP training in Dec 2007. Now, I am a full fledged abap developer. I am not as busy as I was before..so thought of penning down few of my thoughts.
Now, I am trying to acquire new skillsets like WebDynPro, BDT, BTE etc etc..
I jus started learning abap-webdynpro...did 1 or 2 simple applications. I wont say its tough..but u need to understand the architecture, which takes time.
As and when I come across any new things ,I will let you know.
Till then , chao........