Association

  • The object of one class may use the Methods provided by another class. This type of relation is called association
  • It is an loose term and is used to denote any type of dependency that exists between two classes
  • Aggregation and Composition are subsets of composition

Aggregation

  • The object of one Class owns the object of another class
  • When the owning object is destroyed the other object may still continue to exist this type of relation is called aggregation
  • It establishes a “has a” relation between the objects

Composition

  • When the owning object is destroyed the other object will also get destroyed
  • In other words the owning class is responsible for the existence/ lifecycle of the other object
  • It establishes a “has a” relation between the objects