Roles and Responsibilities

An aspect of modeling is to discover the roles and responsibilities of objects. Role and responsibility analysis is applicable to domain objects in general. Here we look specifically at the roles and responsibilities of Entities.

We need some context for the term role. One use, when discussing the Identity and Access Context, is that a Role is an Entity and Aggregate Root that addresses a broad system security concern. Clients can ask if a user is in, or plays, a security role. That’s completely different from what I am now discussing. What I am discussing in this section is how roles can be played by the objects in your model.

Domain Objects Playing Multiple Roles

In object-oriented programming, generally interfaces ...

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