Unit 12: Inheritance, Overriding, and Dynamic Dispatch

Inheritance is useful when a subtype can genuinely stand in for a broader type while preserving its promises.

It is dangerous when used merely to reuse a few lines.

This unit covers:

• extends and subtype relationships;
• inherited members;
• overriding;
• runtime dynamic dispatch;
• substitutability;
• composition-versus-inheritance tradeoffs.

Checkpoint 4 asks you to defend the relationship, not just make a class hierarchy compile.