Java composition example

Aggregation implies a relationship where the child can exist independently of the parent . For example, Bank and Employee, delete the Bank and the Employee still exist. whereas Composition implies a relationship where the child cannot exist independent of the parent.

Benefits of using Composition: Composition allows us to reuse the code . In Java, we can use multiple Inheritance by using the composition concept. The Composition provides better test-ability of a class. Composition allows us to easily replace the composed class implementation with a better and improved version.

Object composition refers to the logical or conceptual structure of the information , not the implementation or physical data structure used to represent it. For example, a sequence differs from a set because (among other things) the order of the composed items matters for the former but not the latter.