Question
What type of relationship is represented by Aggregation
in Object-Oriented Programming?Solution
Aggregation is a "has-a" relationship where one object is composed of other objects, but the lifecycle of the contained objects is independent of the containing object . For example, a Teacher class might be associated with a School class, but even if the School object is destroyed, the Teacher object can continue to exist. Aggregation emphasizes shared ownership and loosely coupled associations, making it useful for scenarios requiring flexibility in object dependencies. Why Other Options Are Incorrect :
- "Is-a" relationship : This refers to Inheritance , where a subclass derives from a parent class.
- "Has-a" relationship with exclusive ownership : This describes Composition , where the contained objects' lifecycle is tied to the container.
- Parent-child relationship : This typically relates to Inheritance or tree structures , not Aggregation.
- Object-to-object message communication : This aligns with Message Passing , which focuses on interaction between objects rather than relationships
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