Java Inheritance

Inheritance is used when the relationship between two classes is a(n) _______ relationship.

• "HAS-A"
• "PART-OF-A"
• "IS-A"
• inverse

The following Syntax is used for?

class Subclass-name extends Superclass-name

{

//methods and fields

}

• Polymorphism

• Encapsulation

• Inheritance

• None of the above

A class that is inherited is called a ______ .

• superclass

• Subclass

• subsetclass

• Relativeclass

What does polymorphism mean?

• Changing shapes
• Having many forms
• Being unchangeable
• Easy

When an object's class is a subclass of a more general class.

• Extension

• Aggregation

• Inheritance

• Dependency

Which Java statement represents inheritance?

• class body inherit Car

• class body super Car

• class body extends Car

• class body this Car

• class body override Car

Which of the following is/are false about inheritance in Java?

I. A subclass inherits all the methods and variables of the superclass.

II. A subclass can override the methods of its superclass

III. A subclass has access to the private instance variables of the superclass.

• I only

• II only

• III only

• I and II only

• I and III only

super keyword is used to access

• only subclass methods

• parent class variables and methods

• subclass variables and methods

• only parent class methods

What is the output of following Java Program?

class Online

{

public

void print()

{

System.out.println("Online::print() called");

}

}

class OOP extends Online

{

public

void print()

{

System.out.println("OOP::print() called");

}

}

public class Main

{

public static void main(String[] args)

{

OOP ob =new OOP();

ob.print();

}

}

• Online::print() called

• OOP::print() called

Consider the following code.

class Vehicle

{

int maxSpeed = 120;

}

class Car extends Vehicle

{

int maxSpeed = 180;

void display() {

System.out.println("Maximum Speed: " + super.maxSpeed);

}

}

/* Driver program to test */

class Test

{

public static void main(String[] args)

{

Car small = new Car(); small.display();

}

}

In the program output, what is the maximum speed displayed?

• 120

• 180

• 120 dan 180

• semua salah