OOPS Interview Questions and Answers in 2025 (100+ Q&A)

OOPS

Ques:- What are the various types of constructors?

Asked In :- worldquant llc,

Right Answer:
There are three main types of constructors:

1. **Default Constructor**: A constructor that does not take any parameters and initializes object members with default values.

2. **Parameterized Constructor**: A constructor that takes parameters to initialize object members with specific values provided during object creation.

3. **Copy Constructor**: A constructor that creates a new object as a copy of an existing object, typically taking a reference to an object of the same class as a parameter.

OOPS

Ques:- What is the difference between new and override?

Asked In :-

Right Answer:
The `new` keyword is used to hide a member of the base class in a derived class, while `override` is used to provide a new implementation of a virtual member of the base class in the derived class.

OOPS

Ques:- How can we call the base method without creating an instance?

Asked In :-

Right Answer:
You can call a base method without creating an instance by using a static method in the base class or by using a derived class that inherits from the base class. For example, in C#, you can use `BaseClass.MethodName()` if the method is static. If it's an instance method, you can call it from a static context by creating a static method in the derived class that calls the base method.

OOPS

Ques:- What are sealed modifiers?

Asked In :-

Right Answer:
Sealed modifiers are used in object-oriented programming to restrict the inheritance of a class. When a class is marked as sealed, it cannot be inherited by other classes, ensuring that its implementation remains unchanged and providing better control over the class hierarchy.

OOPS

Ques:- What are access modifiers?

Asked In :-

Right Answer:
Access modifiers are keywords used in object-oriented programming to set the visibility or accessibility of classes, methods, and variables. The main access modifiers are:

1. **Public**: Accessible from any other class.
2. **Private**: Accessible only within the same class.
3. **Protected**: Accessible within the same class and by derived classes.

OOPS

Ques:- What is an abstraction?

Asked In :-

Right Answer:
Abstraction is the concept of hiding the complex implementation details of a system and exposing only the necessary features or functionalities to the user. It allows focusing on what an object does instead of how it does it.

OOPS

Ques:- Difference between class and an object?

Asked In :-

Right Answer:
A class is a blueprint or template that defines the properties and behaviors (methods) of objects, while an object is an instance of a class that represents a specific entity with its own state and behavior.

OOPS

Ques:- Difference between overloading and overriding?

Asked In :-

Right Answer:
Overloading is when two or more methods in the same class have the same name but different parameters (type, number, or both). Overriding is when a subclass provides a specific implementation of a method that is already defined in its superclass, using the same method name and parameters.

OOPS

Ques:- What are tokens?

Asked In :-

Right Answer:
Tokens are the smallest units of a program that are meaningful to the compiler. In the context of programming languages, tokens can include keywords, identifiers, literals, operators, and punctuation symbols.

OOPS

Ques:- What is exception handling?

Asked In :-

Right Answer:
Exception handling is a programming mechanism that allows developers to manage and respond to runtime errors or exceptional conditions in a controlled way, ensuring that the program can continue to operate or fail gracefully.

OOPS

Ques:- What is an interface?

Asked In :-

Right Answer:
An interface is a contract in object-oriented programming that defines a set of methods that a class must implement, without providing the implementation details. It allows different classes to be treated uniformly based on the methods they support.

OOPS

Ques:- What is method overriding?

Asked In :-

Right Answer:
Method overriding is a feature in object-oriented programming where a subclass provides a specific implementation of a method that is already defined in its superclass, allowing the subclass to customize or replace the behavior of that method.

OOPS

Ques:- What is the super keyword?

Asked In :-

Right Answer:
The `super` keyword is used in object-oriented programming to refer to the superclass (parent class) of the current object. It allows access to superclass methods and constructors.

OOPS

Ques:- What are different types of arguments?

Asked In :-

Right Answer:
The different types of arguments are:

1. **Positional Arguments**: Arguments that are passed to a function in the order they are defined.
2. **Keyword Arguments**: Arguments that are passed to a function using the parameter name.
3. **Default Arguments**: Arguments that take a default value if no value is provided.
4. **Variable-length Arguments**: Arguments that allow you to pass a variable number of arguments to a function, typically using `*args` for non-keyword arguments and `**kwargs` for keyword arguments.

OOPS

Ques:- What is the use of finalize method?

Asked In :-

Right Answer:
The `finalize` method is used to perform cleanup operations on an object before it is garbage collected, allowing the object to release resources or perform any necessary final actions.

OOPS

Ques:- What is a ternary operator?

Asked In :-

Right Answer:
A ternary operator is a shorthand way to write an if-else statement in programming, typically using the syntax `condition ? expressionIfTrue : expressionIfFalse`. It evaluates the condition and returns one of the two expressions based on whether the condition is true or false.

OOPS

Ques:- What is an abstract class?

Asked In :-

Right Answer:
An abstract class is a class that cannot be instantiated on its own and is meant to be subclassed. It can contain abstract methods (without implementation) that must be implemented by derived classes, as well as concrete methods (with implementation).

OOPS

Ques:- What is operator overloading?

Asked In :-

Right Answer:
Operator overloading is a feature in object-oriented programming that allows developers to redefine the behavior of operators (like +, -, *, etc.) for user-defined classes, enabling them to work with objects in a way that is intuitive and similar to built-in types.

OOPS

Ques:- What is function overloading?

Asked In :-

Right Answer:
Function overloading is a feature in object-oriented programming that allows multiple functions to have the same name but differ in the type or number of their parameters.

OOPS

Ques:- What is a friend function?

Asked In :-

Right Answer:
A friend function is a function that is not a member of a class but has access to its private and protected members. It is declared using the `friend` keyword inside the class.

The OOPS (Object-Oriented Programming Systems) category on takluu.com is designed for software developers and programming aspirants who want to strengthen their understanding of object-oriented principles. OOPS is a fundamental programming paradigm used widely across many languages such as Java, C++, Python, and more.

This section covers essential concepts including classes and objects, encapsulation, inheritance, polymorphism, abstraction, and interfaces. You’ll find interview questions that focus on both theory and practical application of these principles in real-world coding scenarios.

Interviewers often ask questions like:

“Explain the four pillars of OOPS.”
“How does inheritance promote code reusability?”
“What is polymorphism and how is it implemented?”

Our content presents these concepts in a simple and clear manner, supported by examples and coding snippets to help you grasp them easily. Whether you’re a beginner or preparing for advanced technical interviews, this category helps you build a strong foundation and confidently tackle OOPS-related questions.

At Takluu, we regularly update the OOPS category with new questions, coding challenges, and best practices to keep you ahead in your interview preparation journey.

Questions in: OOPS

What makes Takluu valuable for interview preparation?

Get Our Mobile App

Programming

Reasoning

Network & Telecom

Management

What makes Takluu valuable for interview preparation?