Method Overriding in Java

Method Overriding in Java:

• If the child class implements the same method present in the parent class again, it is know as method overriding.
• Method overriding helps us to classify a behavior that is specific to the child class.
• The subclass can override the method of the parent class only when the method is not declared as final.
• Example :
• In the below code, we've created two classes: class A & class B.
• Class B is inheriting class A.
• In the main() method, we've created one object for both classes. We're running the meth1() method on class A and B objects separately, but the output is the same because the meth1() is defined in the parent class, i.e., class A.

class A{
    public void meth1() {
        System.out.println("I am method 1 of class A");
    }
}

class B extends A {

}
public class CWH {
    public static void main(String[] args) {
        A a = new A();
        a.meth1();

        B b = new B();
        b.meth1();
    }
}

Output :
I am method 1 of class A
I am method 1 of class A

• Now, let's see how we can override the meth1() for class B :

class A{
    public void meth1() {
        System.out.println("I am method 1 of class A");
    }
}

class B extends A {
    @Override
    public void meth1(){
        System.out.println("I am method 1 of class B");
    }
}
public class CWH1 {
    public static void main(String[] args) {
        A a = new A();
        a.meth1();

        B b = new B();
        b.meth1();
    }
}

Output :
I am method 1 of class A
I am method 1 of class B

Code as described in the video:

class A {
    public int a;
    public int harry() {
        return 4;
    }
    public void meth2() {
        System.out.println("I am method 2 of class A");
    }
}

class B extends A {
    @Override
    public void meth2() {
        System.out.println("I am method 2 of class B");
    }
    public void meth3() {
        System.out.println("I am method 3 of class B");
    }
}

public class cwh_48_method_overriding {
    public static void main(String[] args) {
        A a = new A();
        a.meth2();

        B b = new B();
        b.meth2();
    }
}

Output:
I am method 2 of class A
I am method 2 of class B

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