CHAPTER 51 — Abstract Classes and Polymorphism

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CHAPTER 51 — Abstract Classes and Polymorphism

Classes in a hierarchy are related by the is-a relationship. For example, a Nissan is-a Automobile, and a Sentra is-a Nissan. This chapter discusses how reference variables are used for objects from different classes within a hierarchy. Another subject is the idea of an abstract class — a class that cannot be instantiated but that can be the parent of other classes.

Chapter Topics:

  • Abstract Classes
  • Abstract Methods
  • Polymorphism

QUESTION 1:

How many Valentine cards did you get this year?

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