Method Overriding & @Override

Syntax

@Override\nreturnType methodName(parameters) {\n  // new implementation\n}

Examples

class Animal {
    public void makeSound() {
        System.out.println("Some generic animal sound");
    }
}

class Cat extends Animal {
    @Override
    public void makeSound() {
        System.out.println("Meow!");
    }
}

Animal animal = new Cat();
animal.makeSound();  // Meow! - the overridden version runs

class Shape {
    public double calculateArea() {
        return 0;
    }
}

class Circle extends Shape {
    private double radius = 5;

    @Override
    public double calculateArea() {  // correctly overrides
        return Math.PI * radius * radius;
    }

    // @Override
    // public double calculatearea() {  // typo! lowercase 'a'
    //     return Math.PI * radius * radius;
    // }
    // Without @Override, this typo would silently compile as a brand new,
    // unrelated method instead of overriding calculateArea().
}

class Employee {
    public void work() {
        System.out.println("Doing general work tasks");
    }
}

class Manager extends Employee {
    @Override
    public void work() {
        super.work();  // still do the general work first
        System.out.println("Also managing the team");
    }
}

Manager m = new Manager();
m.work();
// Doing general work tasks
// Also managing the team

Best practices

• Always add @Override when overriding a method - it lets the compiler catch signature mistakes that would otherwise fail silently
• Keep the overriding method's behavior consistent with what the parent class's documentation promises (the Liskov Substitution Principle)
• Use super.methodName() inside an override when you want to extend the parent behavior rather than fully replace it
• Remember private, static, and final methods cannot be overridden - only inherited public/protected instance methods can be

At a glance

Purpose

General-purpose application development

File extension

.java

Runs in

Java Virtual Machine

Usually used with

JDK and Java libraries

Specifications & further reading

• Java Language Specification

Related Java documentation