OOP Quiz: Master Object-Oriented Programming Principles

Questions and Answers

Which of the following is NOT a main principle of OOP?

Code Reusability

What is the purpose of inheritance in Java?

To achieve code reusability

What is a superclass in Java?

A class that is derived from another class

What is method overriding in Java?

The feature that allows a subclass to provide a specific implementation of a method already provided by its superclass Signup and view all the answers

Which of the following best describes encapsulation in object-oriented programming?

The concept of bundling data and methods within a single unit Signup and view all the answers

Which statement best describes the principle of encapsulation?

All important information is contained inside an object and only select information is exposed Signup and view all the answers

What is the purpose of using getter and setter methods in encapsulation?

To provide a public interface for accessing and modifying the data in a class Signup and view all the answers

Study Notes

Object-Oriented Programming (OOP) Principles

Abstraction, Encapsulation, Polymorphism, and Inheritance are the main principles of OOP.

Inheritance in Java

Inheritance allows a new class (subclass or derived class) to inherit the properties and behavior of an existing class (superclass or base class).
The purpose of inheritance is to promote code reuse and facilitate a hierarchical relationship between classes.

Superclass in Java

A superclass is a class from which another class inherits its properties and behavior.

Method Overriding in Java

Method overriding is a process where a subclass provides a specific implementation of a method that is already defined in its superclass.
The subclass method has the same name, return type, and parameter list as the superclass method, but it can have a different implementation.

Encapsulation in OOP

Encapsulation is the concept of bundling data and methods that operate on that data within a single unit, called a class.
It helps to hide the internal implementation details of an object from the outside world and only expose necessary information through public methods.
Encapsulation is about hiding the values or state of a class and only exposing the necessary information to the outside world.

Purpose of Getter and Setter Methods

Getter and setter methods are used to control access to an object's properties, allowing other classes to access or modify the properties while maintaining data integrity.
The purpose of using getter and setter methods is to provide a controlled interface to access and modify an object's state, while hiding the implementation details.