Aggregation
Aggregation is a special form of association where a part-whole relationship exists between objects, and the part (child) can exist independently of the whole (parent). For example, a “Car” object can have an “Engine” object as a part, but the engine can exist outside the car.
What are the Relationships among Objects in OOAD?
In Object-Oriented Analysis and Design (OOAD), the relationship among objects is fundamental to modeling the behavior and structure of a system, and Object diagrams are used to depict instances of classes and their relationships at a specific point in time. There are several types of relationships among objects: