Inheritance - Quiz

Make the Dog class inherit the behavior of the Animal class

Override the start method in the ElectricCar subclass

Which statement best describes inheritance in Java?

What does the extends keyword indicate in a class declaration?

Which use of super is valid inside a subclass method?

When a subclass overrides a non-static method from its superclass, which method is called at runtime?

What happens if a subclass constructor does not explicitly call super(...)?

Which class is at the top of the inheritance hierarchy in Java?

Which statement about the equals method from Object is true if a class does NOT override it?

Which methods a subclass cannot override from its superclass?

In a constructor, what is required if you use super(...)?

Order the steps to create a subclass that overrides a method from its superclass.

Drag and drop to reorder, or use the arrows.

What is the output of this code?

1class Vehicle {
2    String name = "Vehicle";
3    void printName() {
4        System.out.println(name);
5    }
6}
7class Car extends Vehicle {
8    String name = "Car";
9    @Override
10    void printName() {
11        System.out.println(name);
12    }
13}
14public class Main {
15    public static void main(String[] args) {
16        Vehicle v = new Car();
17        v.printName();
18    }
19}

What is the output of this code?

1class Animal {
2    void sound() {
3        System.out.println("Animal");
4    }
5}
6class Dog extends Animal {
7    @Override
8    void sound() {
9        super.sound();
10    }
11}
12public class Main {
13    public static void main(String[] args) {
14        Dog d = new Dog();
15        d.sound();
16    }
17}

What is the output of this code?

1class Base {
2    Base() {
3        System.out.print("Base");
4    }
5}
6class Derived extends Base {
7    Derived() {
8        System.out.print("Derived");
9    }
10}
11public class Main {
12    public static void main(String[] args) {
13        new Derived();
14    }
15}

What is the output of this code?

1class Person {
2    public String toString() {
3        return "Person";
4    }
5}
6public class Main {
7    public static void main(String[] args) {
8        Person p = new Person();
9        System.out.println(p.toString());
10    }
11}

What is the output of this code?

1class Animal {}
2class Dog extends Animal {}
3public class Main {
4    public static void main(String[] args) {
5        Animal a = new Dog();
6        boolean result = a instanceof Dog;
7        System.out.println(result);
8    }
9}

Match each Object class method with its primary purpose.

Click an item on the left, then click its match on the right. Click a matched item to unmatch.

Match each inheritance-related keyword or operator with its role.

Click an item on the left, then click its match on the right. Click a matched item to unmatch.

Complete the code so that Developer inherits from Employee and correctly uses the superclass constructor.

Complete the code so that the overridden start method in Car still calls the Vehicle implementation first.

Complete the code so that the Manager class correctly chains constructors with this and super.

Click the line where the overridden method in Dog is declared.

Click on the line to select.

class Animal {

    void speak() {

        System.out.println("Animal");

    }

}

class Dog extends Animal {

    @Override

    void speak() {

        System.out.println("Dog");

    }

}

public class Main {

    public static void main(String[] args) {

        Animal a = new Dog();

        a.speak();

    }

}