Domain-Driven Design & Object-Oriented Programming

Overview

Domain objects are business logic owners, NOT data containers.

The fundamental principle from Eric Evans: behavior belongs with the data it operates on. When you extract data from an object to calculate something elsewhere, you've violated encapsulation and created what Martin Fowler calls an "Anemic Domain Model" - an anti-pattern.

"The basic symptom of an Anemic Domain Model is that at first blush it looks like the real thing... but when you look at the behavior, you realize there is hardly any behavior on these objects." — Martin Fowler

When to Use