Explain Inheritance in Kotlin | Kotlin Tutorial

In this article, we will learn about the following:

• What is inheritance?
• Example of inheritance

What is Inheritance?

Inheritance is one of the crucial concepts of Object-Oriented language. Inheritance means extending the behavior of one class to another class. In a simple language, it means to inherit the features of an existing class to another class.

There are two types of classes involved in inheritance. 

1. Super Class: It's the main class or parent class from which properties have been inherited to another class.
2. Sub Class: It is the class in which properties inherit. 

Inheritance allows inheriting the properties of multiple classes into another class. 

Syntax:

open class Base(p: Int){  

# class properties  

}  

class Derived(p: Int) : Base(p){  

#class properties

}

Example of inheritance

open class A(name: String, age: Int, salary: Float) {  

   // code of employee  

}  

class B(name: String, age: Int, salary: Float): A(name,age,salary) {  

  // code of programmer  

}  

class C(name: String, age: Int, salary: Float): A(name,age,salary) {  

  // code of salesman  

}

Points to Remember:

• If we want to inherit any class, use the open keyword before the class keyword. 
• All the kotlin classes are final by nature, due to which we have to use the open keyword to make it non-final. 
• Child classes can inherit variables and methods of the parent class. 
• Child class should have only one parent class, but the parent class can have multiple child classes.