Method Overriding in Java: Definition, Rules, and Examples

Method Overriding

Method Overriding is a process in Java where a subclass provides a specific implementation for a method that is already defined in its superclass.

Key Points

1. Method Overriding requires inheritance.
2. To override a method, the subclass method must have the same name, return    type, and parameter list as the superclass method.
3. During method overriding:

• The subclass method definition is used (exposed).
• The superclass method definition is hidden.
• This concept is sometimes referred to as method hiding (though strictly         speaking, method hiding is for static methods).

4. Only instance methods (non-static methods) can be overridden.
5. Method overriding cannot be achieved within the same class; it only works between subclass and superclass.

Example

class Animal {

    void sound() {

        System.out.println("Animal makes a sound");

    }

}

class Dog extends Animal {

    @Override

    void sound() {

        System.out.println("Dog barks");

    }

}

public class Main {

    public static void main(String[] args) {

        Animal a = new Dog();

        a.sound(); // Output: Dog barks

    }

}

Important Notes

• Static methods cannot be overridden (they are hidden instead).
• Method overriding is a runtime polymorphism (dynamic binding) feature in Java.
• The @Override annotation is optional but recommended; it helps the compiler catch mistakes.