Deck 2: Java Object-Oriented Programming

Question 1

Which of the following is a valid declaration of an object of class Box?

A)Box obj = new Box();
B)Box obj = new Box;
C)obj = new Box();
D)new Box obj;

Answer 1

Box obj = new Box();

Question 2

Name the keyword that makes a variable belong to a class, rather than being defined for each instance of the class.

A)static
B)final
C)abstract
D)public

Answer 2

static

Question 3

Variables declared with in a class are called

A)Identifier
B)local variable
C)instance variable
D)global variable

Answer 3

instance variable

Question 4

Variables declared within a method or block are called

A)Static variable
B)local variable
C)instance variable
D)global variable

Question 5

Defining methods with same name and different no. of parameters are called

A)Method overriding
B)method overloading
C)Dynamic method dispatch
D)none of the above

Question 6

_________ is used to initialize objects.

A)Methods
B)arguments
C)constructors
D)new keyword

Question 7

Which of the following is a method having same name as that of its class?

A)finalize
B)delete
C)class
D)constructor

Question 8

Which operator is used by Java run time implementations to free the memory of an object when it is no longer needed?

A)delete
B)free
C)new
D)None of the mentione

Question 9

Which of these access specifiers must be used for main() method?

A)private
B)public
C)protected
D)None of the mentioned

Question 10

Which of these is used to access member of class before object of that class is created?

A)public
B)private
C)static
D)protected

Question 11

The keyword used to create an object

A)class
B)this
C)new
D)malloc

Question 12

The keyword used to refer the current object

A)class
B)this
C)new
D)malloc

Question 13

The method which is automatically invoked during garbage collection.

A)destructor
B)terminate()
C)finalize()
D)destroy()

Question 14

Which class cannot have a subclass in java

A)abstract class
B)parent class
C)final class
D)None of above

Question 15

Which is the keyword used to inherit a class to another?

A)Inherits
B)extends
C)implements
D)import

Question 16

The use of final keyword with method definition

A)Supports method overriding
B)implements dynamic method dispatch
C)Prevents method overriding
D)none of these

Question 17

Identify the type of inheritance when two or more subclasses inherit the properties of a super class.

A)Multiple inheritance
B)Single inheritance
C)Multilevel inheritance
D)Hierarchical inheritance

Question 18

The keyword used inside a class to refer to its immediate super class is

A)super
B)parent
C)base
D)none of these

Question 19

Which of the following is true in the case of abstract class

A)Abstract constructors cannot be created.
B)Abstract classes can not be inherited.
C)An abstract class contains only abstract methods.
D)All of the above.

Question 20

Which of these keywords are used to define an abstract class?

A)abst
B)abstract
C)Abstract
D)abstract class

Question 21

If a class inheriting an abstract class does not define all of its function then it will be known as?

A)abstract
B)A simple class
C)Static class
D)None of the mentioned

Question 22

Which of these is not a correct statement?

A)Every class containing abstract method must be declared abstract.
B)Abstract class defines only the structure of the class not its implementation.
C)Abstract class can be initiated by new operator.
D)Abstract class can be inherited.

Question 23

Which method defined in Integer class can be used to convert a whole number in string type to primitive int type.

A)valueOf()
B)intValue()
C)parseInt()
D)getInteger()

Question 24

The method sqrt() is defined in the class

A)System
B)Root
C)Math
D)Arithmetic