Method Overriding
Learn how subclasses redefine methods of the parent to change or extend behavior.
Method Overriding is a free Java Academy lesson on CoddyKit — lesson 2 of 3. You can read the complete lesson below for free — then practise it hands-on in the browser with a built-in code editor and a 24/7 AI tutor. It is part of the Java Academy learning path, one of 3 lessons in the course, and your progress syncs across the web and the CoddyKit app.
Definition
Method overriding means redefining a parent method in a subclass. The method has the same name, parameters, and return type, but a new body. This lets each subclass provide specific behavior.
Why override?
Overriding allows customization. For example, both Dog and Cat are Animals, but each makes a different sound. Instead of writing new method names, they override the same one for consistent usage.
Rules for overriding
Rules: the method signature must match exactly, the return type must be compatible, and access cannot be more restrictive. Use @Override annotation to catch mistakes at compile time.
Using super.method()
You can still call the parent's method with super.method(). This lets you extend behavior instead of replacing it fully, combining old and new logic in one call.
Mistakes
Mistakes: changing parameter types creates overloading, not overriding. Forgetting @Override can hide typos. Also avoid narrowing access (e.g., public → private) as this causes compile errors.
Code: overriding demo
Code: Dog and Cat override speak() from Animal. Even when referenced as Animal, the subclass version runs, showing true polymorphism.
public class Main {
static class Animal {
void speak() {
System.out.println("Some generic animal sound");
}
}
static class Dog extends Animal {
@Override
void speak() {
System.out.println("Woof!");
}
}
static class Cat extends Animal {
@Override
void speak() {
System.out.println("Meow!");
}
}
public static void main(String[] args) {
Animal a1 = new Dog(); // upcast to Animal
Animal a2 = new Cat();
a1.speak(); // runs Dog version
a2.speak(); // runs Cat version
}
}
Overriding check
Quick check: What does method overriding allow a subclass to do?
Recap
Recap: Overriding redefines methods with the same signature, letting subclasses customize behavior. Use @Override and call super when needed.
Frequently asked questions
Is the “Method Overriding” lesson free?
Yes — the full text of “Method Overriding” is free to read here on the web, and the Java Academy course includes 3 lessons in total. To practise it interactively (a built-in code editor and a 24/7 AI tutor) and unlock the rest of the Java Academy course, upgrade to CoddyKit PRO.
What will I learn in “Method Overriding”?
Learn how subclasses redefine methods of the parent to change or extend behavior. You practise Java Academy with hands-on code you run directly in the browser, and a 24/7 AI tutor answers your questions as you work through the lesson.
Do I need any experience to start Java Academy?
No prior experience is required. Java Academy on CoddyKit is structured for beginners through advanced learners; this is — lesson 2 of 3, so you can start here or from the beginning and move at your own pace.
How long does the “Method Overriding” lesson take?
Most CoddyKit lessons take about 5–10 minutes. Each one is bite-sized and interactive, so you make steady progress and pick up exactly where you left off across the web and the app.
Can I write and run code in this Java Academy lesson?
Yes. Every Java Academy lesson includes a built-in code editor, so you write and run real code right in your browser and get instant AI feedback — no local setup required.
All lessons in this course
- extends & super
- Method Overriding
- Polymorphism & Dynamic Binding