Method Overriding (OOP - JAVA)

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 Method Overriding

Changing the body of a method which comes from a super class to a sub class called method overriding.

The method which is related to the object, run always.

Consider the following example.

class Monkey{

    void climb(){

        System.out.println("Using body");

    }

}

class Man extends Monkey{

    void climb(){

        System.out.println("Using ladder");

    }

}

super class - Monkey

sub class - Man 

if we create a object using Man class,

Man m = new Man();

m.climb();

The output => Using ladder




super keyword

We use super keyword to call the constructor of super class from a sub class.

Always we call the super class from this keyword. We can access the methods and variables inside the super class from a sub class by using super keyword.

Check the following example.

class Monkey{

    Monkey(){

    }

    void climb(){

        System.out.println("Using body");

    }

   void eat(){

        System.out.println("Eating");

    }

}

class Man extends Monkey{

    Man(){

    }

    void climb(){

        System.out.println("Using ladder");

    }

    super();

    super.climb();

    super.eat();

}


You can see how to use method overriding by checking following code examples as well.

ex 1:

public class Human {
    void run(){
        System.out.println("Human can eat");
    }
}
class Gawesh extends Human{
    void run(){
        System.out.println("Gawesh can eat");
    }

    public static void main(String[] args) {
        Gawesh g = new Gawesh();
        g.run();
    }
}

ex 2:

class Samsung extends Mobile{
    public void displayName(){
        System.out.println("Samsung Galaxy Note 22 ULTRA");
        super.displayName();
    }
}
class Apple extends Samsung{
    public void displayName(){
        System.out.println("Iphone 14 Pro Max");
        super.displayName();
    }
}
class Run {
    public static void main(String[] args) {
        Samsung s = new Samsung();
        Apple a = new Apple();
        s.displayName();
        a.displayName();
    }
}


ex 3:

public class CentralBank {
    int getInterestRate(){
        return 0;
    }
}
class BOC extends CentralBank{
    int getInterestRate(){
        return 8;
    }
}
class PeoplesBank extends CentralBank{
    int getInterestRate(){
        return 10;
    }
}
class CommercialBank extends CentralBank{
    int getInterestRate(){
        return 12;
    }
}
class TestOverriding{
    public static void main(String[] args) {
        BOC b = new BOC();
        PeoplesBank p = new PeoplesBank();
        CommercialBank c = new CommercialBank();
        System.out.println("Interest Ratw: " + b.getInterestRate() + "%");
        System.out.println("Interest Ratw: " + p.getInterestRate() + "%");
        System.out.println("Interest Ratw: " + c.getInterestRate() + "%");

    }
}

I think, you can try above coding examples on your own IDE and understand how we can apply method overriding practically. 


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