Java 6 Illuminated: An Active Learning Approach, 2nd Edition

10.9 Chapter Summary 717

CHAPTER SUMMARY

10.9 Chapter Summary

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Inheritance lets us organize related classes into ordered levels of

functionality, called hierarchies. The advantage is that we write the

common code only once and reuse it in multiple classes.

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A subclass inherits methods and fields of its superclass.A subclass can

have only one direct superclass, but many subclasses can inherit from

a common superclass.

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Inheritance implements the “is a” relationship between classes. Any

object of a subclass is also an object of the superclass.

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All classes inherit from the Object class.

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To specify that a subclass inherits from a superclass, the subclass ...