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Module 7: Advanced Object-Oriented Concepts

Lesson focus

Abstract Classes vs Interfaces

Choose the right construct to model shared behavior, default implementations, and optional capabilities.

Abstract classes excel at sharing partial implementations and state; interfaces define capabilities across unrelated types.

Java 8+ interfaces support default and static methods—use them sparingly to avoid building “god interfaces.”

Document extension points clearly: abstract methods signal required overrides, while default methods provide safe fallbacks.

Lesson quiz

Which construct allows multiple inheritance of type in Java?

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