I'm currently designing a web application using DDD methodology. While distinguishing the Entities from value objects, I came across one such model element which I'm unable to decide to place under Entity /VO category.
Every Order will be associated with 1 and only 1 Comment History object which manages the List of Comments. Now when the order is edited, a user may add a comment. This gets appended to the comment history.
Comment History object as such doesn't mean anything when it comes to persistance. I'm planning to use nHibernate "component" so effectively only the list of comments gets written down to ORDER_COMMENTS table.
Order is an Entity.
Should Comment History (Various user's comments appended to the Order) be an Entity or VO?
From my point of view I see the comment history as the value object, I mean, a comment history is just a collection of comments at a given time. despite the fact that you can reconstruct or not the comment history every time you add an comment to it, it does not have an identity and lifecicle of its own.
I mean if you have to comment histories with the same comments do we have two different comment histories? I do not think so, we have the same comment history, we do not care about the identity we care about the attributes, i.e. the comments inside the comment history to be the same.
So that for me the comment history is a V.O.
Thanks Pablo