Method overriding in Java - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to override the method display in the subclass.

Java

class Parent {
    void display() {
        System.out.println("Parent display");
    }
}

class Child extends Parent {
    @Override
    void [1]() {
        System.out.println("Child display");
    }
}

Drag options to blanks, or click blank then click option'

Aoutput

Bshow

Cprint

Ddisplay

Attempts:

3 left

💡 Hint

Common Mistakes

Using a different method name in the subclass.

Forgetting the @Override annotation (though optional, it helps).

The method name in the subclass must exactly match the method name in the parent class to override it.

2fill in blank

medium

Complete the code to call the overridden method from the subclass object.

Java

class Parent {
    void greet() {
        System.out.println("Hello from Parent");
    }
}

class Child extends Parent {
    @Override
    void greet() {
        System.out.println("Hello from Child");
    }
}

public class Test {
    public static void main(String[] args) {
        Child obj = new Child();
        obj.[1]();
    }
}

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Agreet

BsayHello

Chello

Ddisplay

Attempts:

3 left

💡 Hint

Common Mistakes

Calling a method name that does not exist in the class.

Using the parent class method name incorrectly.

To call the overridden method, use the exact method name defined in the class, which is greet.

3fill in blank

hard

Fix the error in the method overriding by completing the method signature correctly.

Java

class Animal {
    void sound() {
        System.out.println("Animal sound");
    }
}

class Dog extends Animal {
    @Override
    public [1] sound() {
        System.out.println("Bark");
    }
}

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Adouble

Bvoid

CString

Dint

Attempts:

3 left

💡 Hint

Common Mistakes

Changing the return type in the overriding method.

Adding a return statement when the parent method returns void.

The return type of the overriding method must match the parent method's return type, which is void here.

4fill in blank

hard

Fill both blanks to override the method and call the parent class method inside the overriding method.

Java

class Vehicle {
    void start() {
        System.out.println("Vehicle started");
    }
}

class Car extends Vehicle {
    @Override
    void [1]() {
        super.[2]();
        System.out.println("Car started");
    }
}

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Astart

Brun

Dbegin

Attempts:

3 left

💡 Hint

Common Mistakes

Using different method names in override and super call.

Forgetting to call the parent method if needed.

The method name must be start to override, and super.start() calls the parent method.

5fill in blank

hard

Fill all three blanks to override the method with a parameter and call the parent method with the same parameter.

Java

class Printer {
    void print(String message) {
        System.out.println("Printer: " + message);
    }
}

class ColorPrinter extends Printer {
    @Override
    void [1](String [2]) {
        super.[3]([2]);
        System.out.println("ColorPrinter: " + [2]);
    }
}

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Aprint

Bmessage

Dtext

Attempts:

3 left

💡 Hint

Common Mistakes

Using different method or parameter names.

Not passing the parameter to the parent method.

The method name is print, the parameter name is message, and the parent method is called with super.print(message).