Composition Relationships

We have already seen that composition represents a part of a whole. Although the inheritance relationship is stated in terms of is-a, composition is stated in terms of has-a. We know intuitively that a car “has-a” steering wheel (see Figure 9.2).

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Figure 9.2. A composition relationship.

The reason to use composition is that it builds systems by combining less complex parts. This is a common way for ...

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