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Chapter 6
Structural Design
B
, we examine how class designs
may be used together. We cover the basic relationships modeled in
Object-Oriented Design (OOD): has-a, holds-a, and is-a. ese relation-
ships are also known as composition, containment, and inheritance,
respectively. Each type of relationship is examined in detail, with exam-
ples and descriptions of intended use. e relevance, costs, and benets of
each design are evaluated. A comparative evaluation of these relationships
reinforces the underlying impetus for each design.
Understanding OOD is important for constructing reliable, large-scale
systems