Object-Oriented Programming in Java

Object-Oriented Programming in Java — Multiple Inheritance

Multiple Inheritance occurs when a class is derived from more than one base class, i.e. when a class has more than one immediate parent class. For example 1. A Hyundai Elantra IS A Car 2. A Hyundai Elantra IS A Sedan as well

A class in Java cannot extend from more than one class. As a result, the question of “how can we implement multiple inheritances” arises. Interfaces are the answer to the preceding question. Interfaces can be used to implement multiple inheritances in Java. A class may implement multiple interfaces, and an interface may extend from multiple interfaces.

Take the same example mentioned above. That can be implemented using the following.

1. A base class named Car 2. An interface named IsSedan 3. An Elantra class derived from Car and implementing IsSedan

The above illustration then becomes,

Image by Author

Implementation in Java

The output is

The model of Elantra is: 2019 The manufacturer of Elantra is: Hyundai The variant of Elantra is: Sport The bootspace of Elantra is: 420 litres

The model of Elantra is: 2018 The manufacturer of Elantra is: Hyundai The variant of Elantra is: Eco The bootspace of Elantra is: 420 litres

Interface vs Abstract Class

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