composition-over-inheritance

To refactor inheritance to composition, extract shared behaviors into small composable units or interfaces, then inject and wire these capabilities into concrete classes instead of extending concrete parents, reducing tight coupling and rigid hierarchies.

Inheritance creates tight coupling because subclasses deeply depend on the implementation details of their concrete parents, forming rigid hierarchies. Composition solves this by enabling runtime behavior injection and combining mixable, interface-based capabilities.

The best way to mix and match object behaviors is using composition over inheritance. Define capabilities as interfaces or small composable objects, and wire them into classes to enable runtime behavior injection and flexible component reuse.

You need to replace is-a class relationships when facing rigid hierarchies or needing mixable behaviors. Converting is-a inheritance into a set of composable capabilities allows you to combine behaviors dynamically and avoid deep inheritance trees.

Yes, you can inject runtime behaviors by defining capabilities as small composable units or interfaces and wiring them into your classes. This composition approach avoids extending concrete parents and enables flexible behavior injection.

Using composition over inheritance shifts complexity from class hierarchies to object wiring. While it safely avoids deep inheritance and enables runtime behavior injection, it requires carefully designing interface-based capabilities to ensure components mix cohesively without tight coupling.