Master Java Programming Fundamentals: Online Learning Quizzes

Question 1

Which of the following data types can **NOT** be used in Java?

Accepted Answer

string

Answer

int

Answer

boolean

Question 2

Which of the following data types is **not** supported by Java?

Accepted Answer

string

Answer

int

Answer

boolean

Answer

float

Question 3

In Java, what is the correct syntax for an if statement?

Accepted Answer

if (condition) { statement(s); }

Answer

if (condition) : statement(s);

Answer

if (condition) statement(s)

Answer

if condition  { statement(s); }

Question 4

What is the primary purpose of a try-catch block in Java?

Accepted Answer

To handle exceptions and prevent program termination.

Answer

To create new objects.

Answer

To loop through a set of data.

Answer

To define a method.

Question 5

Which syntax is used to create a new object in Java?

Accepted Answer

Class_name objectName = new Class_name();

Answer

Class_name() objectName = new Class_name();

Answer

new Class_name objectName();

Answer

objectName Class_name = new Class_name();

Question 6

What is the role of the 'this' keyword in Java?

Accepted Answer

To refer to the current object instance.

Answer

To call a method from another class.

Answer

To create a new object instance.

Question 7

How does a constructor differ from a method in Java?

Accepted Answer

A constructor initializes an object, while a method operates on an object.

Answer

A constructor has a return type, but a method does not.

Answer

A method is static, but a constructor is not.

Question 8

What is the output of the following Java code?
int x = 5;
x++;
System.out.println(x);

Accepted Answer

6

Answer

5

Answer

7

Answer

Error

Question 9

In Java, what is the correct syntax to declare an integer variable named 'num'?

Accepted Answer

int num;

Answer

Int num;

Answer

int Num;

Answer

integer num;

Question 10

Consider the following Java code: System.out.println("Hello" + 10); What will be the output?

Accepted Answer

Hello10

Answer

Error: Type mismatch

Answer

10

Answer

10Hello

Question 11

What is the primary purpose of the 'this' keyword in Java?

Accepted Answer

To refer to the current object

Answer

To call a constructor

Answer

To access static members

Answer

To declare an inner class

Question 12

Which exception is thrown when an attempt is made to access an array element that is beyond the array's bounds?

Accepted Answer

ArrayIndexOutOfBoundsException

Answer

IndexOutOfBoundsException

Answer

IllegalArgumentException

Answer

NullPointerException

Question 13

In Java, what is the key difference between a 'method' and a 'constructor'?

Accepted Answer

A constructor initializes an object, while a method performs an action on an object.

Answer

A constructor has no return type, while a method returns a value.

Answer

A constructor is called explicitly, while a method is called implicitly.

Question 14

In Java, what is the primary purpose of the 'super' keyword?

Accepted Answer

To invoke the constructor of the superclass

Answer

To access the methods of the superclass

Answer

To declare an abstract method

Answer

To cast an object to a superclass type

Question 15

Which Java data structure is designed to store a collection of unique, unordered elements?

Accepted Answer

HashSet

Answer

ArrayList

Answer

LinkedList

Answer

HashMap

Question 16

What will be the output of the following Java code: int x = 5; x += 3; System.out.println(x);

Accepted Answer

8

Answer

5

Answer

Error: Assignment to final variable

Answer

3

Question 17

What is the correct syntax for a for loop in Java?

Accepted Answer

for (initialization; condition; increment) { }

Answer

do { } while (initialization; condition; increment);

Answer

for (condition; initialization; increment) { }

Answer

while (initialization; condition; increment) { }

Question 18

Which keyword is used to declare a public method in Java?

Accepted Answer

public

Answer

protected

Answer

static

Answer

private

Question 19

What is the purpose of the 'this' keyword in Java?

Accepted Answer

To refer to the current object

Answer

To call a constructor

Answer

To access static members

Answer

To create a new object

Question 20

Which of the following is a checked exception in Java?

Accepted Answer

IOException

Answer

NullPointerException

Answer

ArrayIndexOutOfBoundsException

Answer

ArithmeticException

Question 21

What is the key difference between a class and an interface in Java?

Accepted Answer

A class can be instantiated, while an interface cannot.

Answer

A class can have multiple implementations, while an interface cannot.

Answer

An interface can be inherited, while a class cannot.

Question 22

What is the result of the following Java code snippet:

System.out.println(5 + "" + 5);

Accepted Answer

55

Answer

10

Answer

Compilation error

Answer

5

Question 23

What is the correct syntax to create an instance of a class in Java?

Accepted Answer

ClassName objectName = new ClassName();

Answer

ClassName new objectName = ClassName();

Answer

objectName = new ClassName();

Answer

new ClassName() = objectName;

Question 24

What is the primary purpose of the 'super' keyword in Java?

Accepted Answer

To invoke the constructor of the parent class

Answer

To override methods in the parent class

Answer

To access the static members of the parent class

Answer

To create a new object of the parent class

Question 25

Which data type in Java is used to store a single character?

Accepted Answer

char

Answer

float

Answer

int

Answer

byte

Question 26

In Java, what is the primary purpose of the 'this' keyword?

Accepted Answer

To refer to the current object instance.

Answer

To create a new object.

Answer

To call a method from a parent class.

Answer

To access static members of a class.

Question 27

Which of the following is a valid control flow statement in Java?

Accepted Answer

while

Answer

until

Answer

repeat

Question 28

In Java, what is an interface primarily used for?

Accepted Answer

Declaring method signatures that must be implemented by classes.

Answer

Storing multiple values in a single variable.

Answer

Creating abstract classes.

Question 29

What is the key distinction between a checked and an unchecked exception in Java?

Accepted Answer

Checked exceptions must be explicitly handled, while unchecked exceptions are handled automatically.

Answer

Checked exceptions are more severe than unchecked exceptions.

Answer

Checked exceptions are thrown at compile time.

Question 30

Which of the following is a valid access modifier in Java?

Accepted Answer

public

Answer

protected-private

Answer

global

Answer

final-static

Question 31

What is the primary purpose of a constructor in Java?

Accepted Answer

To initialize an object when it is created.

Answer

To declare the methods of an object.

Answer

To provide default values for object variables.

Question 32

Which of the following is NOT a primitive data type in Java?

Accepted Answer

String

Answer

double

Answer

int

Answer

boolean

Question 33

Consider the following Java code: int x = 10; x += 2; System.out.println(x); What will be the output?

Accepted Answer

12

Answer

8

Answer

10

Question 34

Which access modifier in Java allows a method to be accessed by classes within the same package and subclasses?

Accepted Answer

protected

Answer

default

Answer

public

Answer

private

Question 35

Which of the following is a valid primitive data type in Java?

Accepted Answer

int

Answer

string

Answer

array

Answer

uint

Question 36

What is the primary purpose of the 'break' keyword in a Java switch statement?

Accepted Answer

To terminate the execution of the switch block immediately.

Answer

To execute all cases in the switch block.

Answer

To continue to the next case in the switch block.

Answer

To evaluate the switch expression.

Question 37

Which of the following access modifiers can be used to restrict access to a Java class from outside the package?

Accepted Answer

private

Answer

virtual

Answer

static

Answer

final

Question 38

What is the purpose of the 'throws' keyword in a Java method declaration?

Accepted Answer

To declare that the method may throw a specific exception.

Answer

To handle exceptions that are thrown by the method.

Answer

To catch exceptions that may be thrown by the method.

Question 39

Which of the following is a valid logical operator in Java?

Accepted Answer

&&

Answer

===

Answer

->

Answer

//

Question 40

What is the primary purpose of the 'super' keyword in a Java constructor?

Accepted Answer

To invoke the constructor of the superclass.

Answer

To override the superclass's methods.

Answer

To access the superclass's fields.

Answer

To create a new instance of the superclass.

Question 41

What is the primary distinction between a Java class and an object?

Accepted Answer

A class is a blueprint or template, while an object is an instance of the class.

Answer

An object is a blueprint, while a class is an instance of an object.

Answer

Classes and objects are essentially the same concept.

Question 42

Which of the following is a primary advantage of utilizing Java's garbage collector?

Accepted Answer

Automated memory management

Answer

Enhanced program speed

Answer

Reduced code complexity

Answer

Increased program security

Question 43

What is the primary function of the 'import' statement in Java?

Accepted Answer

To incorporate classes or packages from other libraries or the Java API.

Answer

To define custom classes or interfaces.

Answer

To execute specific code blocks conditionally.

Question 44

Which Java data type is suitable for representing whole numbers without decimal parts?

Accepted Answer

int

Answer

float

Answer

boolean

Answer

char

Question 45

What is the primary purpose of the 'this' keyword in Java?

Accepted Answer

Refer to the current object instance within a method

Answer

Invoke a constructor

Answer

Access static class members

Answer

Declare local variables

Question 46

What is the Java class that specifically represents logical values of true or false?

Accepted Answer

Boolean

Answer

Integer

Answer

String

Question 47

Which of the following is not a valid access modifier in Java?

Accepted Answer

publicly

Answer

private

Answer

protected

Answer

default

Question 48

Which Java operator is used for concatenating two strings?

Accepted Answer

+

Answer

==

Answer

&

Answer

|

Question 49

Which Java exception is specifically thrown when attempting to divide a number by zero?

Accepted Answer

ArithmeticException

Answer

NullPointerException

Answer

InputMismatchException

Answer

IndexOutOfBoundsException

Question 50

Which Java modifier restricts access to a class member, making it accessible only within the class itself?

Accepted Answer

private

Answer

default

Answer

protected

Answer

public

Question 51

What is the primary function of the 'import' statement in Java?

Accepted Answer

To incorporate classes and packages from external sources into your Java program

Answer

To define new classes within your program

Answer

To include external libraries into your program