CodeSignal Technical Assessment Object-Oriented Programming

Question 1

What is encapsulation in object-oriented programming?

Accepted Answer

Bundling data and methods within a class while restricting direct access to internal state

Answer

Encapsulation bundles data and the methods that operate on it into a single unit (class) while hiding internal state from outside access.

Question 2

Which keyword is used in Java, C++, and JavaScript to create a new instance of a class?

Accepted Answer

new

Answer

The `new` keyword allocates memory and invokes the constructor to create a new object instance in most OOP languages.

Question 3

What is inheritance in object-oriented programming?

Accepted Answer

A mechanism where one class acquires the properties and methods of another class

Answer

Inheritance allows a child (subclass) to acquire attributes and behaviors from a parent (superclass), enabling code reuse and hierarchical classification.

Question 4

What is a constructor in OOP?

Accepted Answer

A special method automatically called when a new object is created

Answer

A constructor is a special method automatically invoked upon object creation, used to initialize the object's fields and set its initial state.

Question 5

What does the `this` keyword (or `self` in Python) refer to inside an instance method?

Accepted Answer

The current instance of the class on which the method is called

Answer

`this` / `self` is a reference to the current object instance, allowing methods to access and modify the object's own properties.

Codesignal Practice Test

Codesignal Practice Test

CodeSignal Technical Assessment Object-Oriented Programming