Using constant fields vs initial data

Question

Hi,

I'm designing some new class diagrams for extending an existing office automation application. In a special case I have an option to use extra fields on Entity1 to determine something or use additional data rows in Entity2 to determine that. I believe first approach is better because it does not force us to insert initial data while deploying our application in new installations but the BOSS insists that the second approach is better because it injects no change into current class diagrams (Entity1 and Entity2 both exist now and are in use).

I'm wondering which one is really better and if I'm right, so how can I convince him that my approach is better?

UPDATE: In the following class diagram, SendingInforamtion is Entity1 and LetterStatus is Entity2.

[If image is not visible try clicking here or here

Answer 1

It is really hard to say for certain without seeing the whole program, knowing the whole situation, and knowing the intended implementation. Having said that if I remember right one of the key points in object oriented programming is the creation and re-use of objects. If there is a way to reuse the existing entities (if I am understanding the question properly) than I believe that may be the most cost effective way to go about solving this problem. Also you have to look at where else the two entities are used and how any changes to this code would effect their other uses. Hope this was at least a little help for you.