Interactive MCQ Quiz

What is the primary advantage of Java’s bytecode?

a) It executes faster than native code

b) It provides platform independence

c) It reduces program size

d) It eliminates the need for compilation

Which of the following is NOT a feature of Object-Oriented Programming
in Java?

a) Encapsulation

b) Polymorphism

c) Pointer arithmetic

d) Inheritance

What is the role of the Java Virtual Machine (JVM)?

a) To compile Java source code

b) To execute Java bytecode

c) To debug Java programs

d) To create Java documentation

Which access specifier provides the most restrictive access in Java?

a) public

b) protected

c) default (package-private)

d) private

What happens when an object is no longer referenced in Java?

a) It is immediately deleted from memory

b) It becomes eligible for garbage collection

c) It throws a NullPointerException

d) It is moved to permanent storage

Which keyword is used to prevent method overriding in Java?

a) static

b) final

c) abstract

d) const

What is the purpose of the this keyword in Java?

a) To refer to the parent class

b) To refer to the current object instance

c) To create a new object

d) To import packages

In Java, method overloading is an example of:

a) Runtime polymorphism

b) Compile-time polymorphism

c) Inheritance

d) Encapsulation

Which statement about static methods is TRUE?

a) They can access instance variables directly

b) They can be overridden in subclasses

c) They belong to the class rather than instances

d) They must be declared as final

Q10

What is the difference between mutable and immutable strings in Java?

a) Mutable strings can be changed after creation, immutable cannot

b) Immutable strings are faster than mutable strings

c) Mutable strings use less memory

d) There is no difference

Q11

Which class in Java represents an immutable string?

a) StringBuilder

b) StringBuffer

c) String

d) CharSequence

Q12

What is the purpose of command line arguments in Java?

a) To pass parameters to the main method at runtime

b) To import libraries

c) To define class variables

d) To handle exceptions

Q13

Which class is used for reading keyboard input with better performance?

a) InputStream

b) Scanner

c) BufferedReader

d) FileReader

Q14

What is the correct order of constructor calling in multilevel inheritance?

a) Child to parent

b) Parent to child

c) Random order

d) Only child constructor is called

Q15

The super keyword is used to:

a) Call the superclass constructor or methods

b) Create a new superclass

c) Override methods

d) Define static methods

Q16

What is dynamic method dispatch in Java?

a) Calling methods at compile time

b) Runtime resolution of overridden methods

c) Creating multiple methods with same name

d) Dispatching threads dynamically

Q17

Which statement about abstract classes is TRUE?

a) They can be instantiated directly

b) They can contain both abstract and concrete methods

c) They cannot have constructors

d) They must contain only abstract methods

Q18

What is the main difference between an interface and an abstract class?

a) Interfaces cannot have any methods

b) abstract classes support multiple inheritance, interfaces do not

c) Interfaces support multiple inheritance, abstract classes do not

d) There is no difference

Q19

In Java, all interface methods are implicitly:

a) private and final

b) public and abstract (prior to Java 8)

c) protected and static

d) default and synchronized

Q20

What is the purpose of creating packages in Java?

a) To improve program execution speed

b) To organize classes and avoid naming conflicts

c) To reduce file size

d) To enable multithreading

Q21

Which keyword is used to import all classes from a package?

a) import package.*;

b) include package.*;

c) using package.*;

d) require package.*;

Q22

What is an exception in Java?

a) a syntax error

b) an event that disrupts normal program flow

c) a compilation error

d) a warning message

Q23

Which block is always executed in exception handling,
regardless of whether an exception occurs?

a) try

b) catch

c) finally

d) throw

Q24

What is the difference between throw and throws?

a) throw is used to declare exceptions, throws is used to throw them

b) throw is used to explicitly throw an exception, throws declares exceptions

c) They are identical keywords

d) throw is for checked exceptions, throws is for unchecked

Q25

Which exception type must be explicitly handled or declared?

a) RuntimeException

b) NullPointerException

c) Checked exceptions

d) arithmeticException

Q26

How do you create a user-defined exception class?

a) Extend the Exception or RuntimeException class

b) Implement the Exception interface

c) Use the @Exception annotation

d) Declare it as final

Q27

What is multithreading in Java?

a) Running multiple programs simultaneously

b) Executing multiple threads concurrently within a program

c) Creating multiple classes

d) Using multiple processors

Q28

Which method starts a thread’s execution?

a) run()

b) start()

c) execute()

d) begin()

Q29

What are the two ways to create a thread in Java?

a) Extending Thread class or implementing Callable interface

b) Extending Thread class or implementing Runnable interface

c) Implementing Runnable or Executable interfaces

d) Using ThreadPool or ThreadExecutor

Q30

What is the main thread in Java?

a) The thread with highest priority

b) The thread that starts when the program begins

c) The thread that handles user input

d) The thread that performs garbage collection

Q31

Which method is used to set thread priority?

a) setPriority(int)

b) setThreadPriority(int)

c) priority(int)

d) changePriority(int)

Q32

What is thread synchronization?

a) Running threads in sequence

b) Coordinating thread access to shared resources

c) Creating threads simultaneously

d) Terminating threads together

Q33

Which keyword is used to synchronize a method or block?

a) sync

b) synchronized

c) lock

d) mutual

Q34

What is a deadlock in multithreading?

a) When a thread terminates unexpectedly

b) When two or more threads wait indefinitely for resources held by each other

c) When a thread has the highest priority

d) When a thread is suspended permanently

Q35

Which method is used to suspend a thread temporarily?

a) pause()

b) wait()

c) stop()

d) sleep()

Q36

What is the purpose of the finalize() method?

a) To initialize objects

b) To perform cleanup before garbage collection

c) To terminate the program

d) To create final variables

Q37

In Java, parameters are passed to methods by:

a) Call by reference for all types

b) Call by value for all types

c) Call by reference for objects, call by value for primitives

d) Call by value, but object references are passed as values

Q38

What is a nested class?

a) a class defined inside a package

b) a class defined within another class

c) a class that extends another class

d) a class with multiple constructors

Q39

Which of the following about inner classes is TRUE?

a) They cannot access outer class members

b) They can access all members of the outer class

c) They must be declared as static

d) They cannot be instantiated

Q40

What is encapsulation in Java?

a) Bundling data and methods that operate on that data within a class

b) Creating multiple classes

c) Inheriting properties from parent class

d) Overriding methods

Q41

Which principle allows a subclass object to be treated
as a superclass object?

a) Encapsulation

b) abstraction

c) Polymorphism

d) Composition

Q42

What is the purpose of garbage collection in Java?

a) To delete unused variables

b) To automatically reclaim memory occupied by unreferenced objects

c) To remove syntax errors

d) To optimize code execution

Q43

Which of these is a valid thread state in Java?

a) start, run, stop

b) active, inactive, sleeping

c) new, runnable, terminated

d) created, executing, finished

Q44

What happens when a method in a subclass has the same signature
as in the super class?

a) Compilation error

b) Method overloading

c) Method overriding

d) Method hiding

Q45

Which exception is thrown when dividing by zero in integer arithmetic?

a) NullPointerException

b) arithmeticException

c) NumberFormatException

d) DivisionException

Q46

What is the Scanner class used for?

a) Scanning files for viruses

b) Parsing primitive types and strings from input sources

c) Scanning network connections

d) Debugging code

Q47

Which access level allows access within the same package and subclasses?

a) private

b) default

c) protected

d) public

Q48

What is abstraction in OOP?

a) Hiding implementation details and showing only functionality

b) Creating multiple objects

c) Inheriting from multiple classes

d) Overloading methods

Q49

Which class should be used for mutable string operations with thread safety?

a) String

b) StringBuilder

c) StringBuffer

d) Chararray

Q50

What is the default priority of the main thread?

a) 1

b) 5

c) 10

d) 0

MCQ Attempted/Unattempted

MCQ on Advanced Java (MCA-301)