Object composition in Java

Composition offers better test-ability of a class than Inheritance . If one class consists of another class, you can easily construct a Mock Object representing a composed class for the sake of testing. This privilege is not given by inheritance.

Composition offers better test-ability of a class than Inheritance . If one class consists of another class, you can easily construct a Mock Object representing a composed class for the sake of testing. This privilege is not given by inheritance.

Composition relationships are part-whole relationships where the part must constitute part of the whole object . For example, a heart is a part of a person’s body. The part in a composition can only be part of one object at a time.

Composition relationships are part-whole relationships where the part must constitute part of the whole object . For example, a heart is a part of a person’s body. The part in a composition can only be part of one object at a time.

This is a layered model of system construction (design) where a single component references others only through their (public/export) interfaces . The horizontal structure relates different components of same realm that can play the same role in the same layer.

This is a layered model of system construction (design) where a single component references others only through their (public/export) interfaces . The horizontal structure relates different components of same realm that can play the same role in the same layer.

Inheritance and composition are two programming techniques developers use to establish relationships between classes and objects. Whereas inheritance derives one class from another, composition defines a class as the sum of its parts .