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Module 7: Advanced Object-Oriented Concepts

Lesson focus

Composition vs Inheritance

Decide when delegation beats inheritance and how to migrate brittle hierarchies toward composition.

Composition wraps functionality from other classes, allowing runtime substitution and better testability.

Refactor deep hierarchies by extracting reusable collaborators (e.g., MovementController, Renderer).

Document design decisions so future maintainers know why composition or inheritance was chosen.

Lesson quiz

Which advantage does composition offer over inheritance?

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