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Study and learn Interview MCQ Questions and Answers on Java Classes and Objects. Attend job interviews easily with these Multiple Choice Questions. You can print these Questions in default mode to conduct exams directly. You can download these MCQs in PDF format by Choosing Print Option first and Save as PDF option next using any Web Browser.
Go through Java Theory Notes Classes and Java Theory Notes on Objects before reading these objective questions.
1) Java is a ___ programming language.
A) Functional
B) Object-Oriented
C) Theoretical
D) All the above
Answer [=]
B
Explanation:
Everything in Java is implemented using Object-Oriented principles.
2) In Java programming language, the code is placed inside ___.
A) Classes, Interfaces
B) Methods
C) Blocks
D) All the above
Answer [=]
D
3) Properties are implemented using ___ in Java.
A) Methods
B) Variables
C) Interfaces
D) All the above
Answer [=]
B
4) A Class in Java is like a ____.
A) Prototype
B) Instruction Sheet
C) Blueprint
D) All the above
Answer [=]
D
5) Which is the file extension used for a public Java class source code?
A) .j
B) .class
C) .java
D) None
Answer [=]
C
6) Which is the file extension used for a compiled Java class file?
A) .j
B) .java
C) .class
D) .cls
Answer [=]
C
7) State TRUE or FALSE. The source-code of An Abstract-Class or Interface is kept inside a .java file.
A) FALSE
B) TRUE
C) –
D) –
Answer [=]
B
8) After compilation, an Interface or Abstract-Class is kept in a ___ file in Java programming.
A) .java
B) .cls
C) .class
D) .interface
Answer [=]
C
Explanation:
All compiled Java classes, interfaces and abstract classes are kept in a .class file only. All source files are kept in .java files.
9) State TRUE or FALSE. In Java, a public class or abstract-class or interface must be kept in a separate .java file.
A) FALSE
B) TRUE
C) –
D) –
Answer [=]
B
10) In a .java file, how many numbers of public types namely class, interface or abstract can be managed?
A) 1
B) 2
C) 3
D) Any number
Answer [=]
A
Explanation:
Only one public type is allowed per .java file.
11) In Java, the keyword used to declare a class is ___.
A) Class
B) Java
C) class
D) java
Answer [=]
C
12) A Java class can contain___.
A) Variables
B) Methods, Constructors
C) Inner Classes (A class inside another class)
D) All the above
Answer [=]
D
13) How many maximum numbers of objects can be created from a single Class in Java?
A) 32
B) 64
C) 256
D) None
Answer [=]
D
Explanation:
There is no limit on the number of objects being created from a class.
14) Creating an object from a class is also called ____.
A) Initializing
B) Instantiating
C) Interfacing
D) None of the above
Answer [=]
B
15) The keyword used to create a new object in Java is ___.
A) class
B) java
C) new
D) create
Answer [=]
C
16) Choose the correct statements about choosing a name for a class in Java.
A) The class name can start with only a letter or underscore or dollar sign.
B) The class name can contain numbers
C) The class name can not start with a number
D) All the above
Answer [=]
D
Explanation:
These are also called Java naming rules.
17) An object is created at __ time in Java.
A) Compile-time
B) Run time
C) Assembling time
D) None of the above
Answer [=]
B
18) Choose the correct statement about Java main method.
A) The main method is not a required method
B) The main method must be declared public static void.
C) you can define program flow using the main method. The Java virtual machine calls the main method directly.
D) All the above
Answer [=]
D
Explanation:
Java compiler does not complain about a missing main method.
19) Choose the correct syntax for declaring a Java class below.
A)
class CLASSNAME
{
}
B)
CLASSNAME class
{
}
C)
class CLASSNAME;
{
}
D)
Class CLASSNAME
{
}
Answer [=]
A
Explanation:
Use the keyword class but not Class.
20) Choose the correct way of creating an object of the below class.
class Table
{
Table(){System.out.println(“Table Created”);}
}
A)
Table t = new Table;
B)
Table t = new Table();
C)
Table() t = new Table();
D) None of the above
Answer [=]
B