| ... | ... | @@ -10,7 +10,7 @@ An Association classifies a set of tuples representing links between typed insta |
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Aggregation and Composition are subsets of associations meaning they are specific cases of association.
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In both aggregation and composition object of one class "owns" object of another class. But there is a subtle difference:
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* Aggregation implies a relationship where the child can exist independently of the parent. Example: Class (parent) and Student (child). Delete the Class and the Students still exist.
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* Aggregation implies a relationship where the child can exist independently of the parent. Example: Lecture (parent) and Student (child). Delete the Lectureand the Students still exist.
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* Composition implies a relationship where the child cannot exist independent of the parent. Example: House (parent) and Room (child). Rooms don't exist separate to a House.
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