Object-Oriented Design (OOD) Learning Quizzes for Software Engineering Masters

Question 1

Which principle is NOT a fundamental tenet of Object-Oriented Design (OOD)?

Accepted Answer

Modularity

Answer

Encapsulation

Answer

Inheritance

Answer

Abstraction

Question 2

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

Accepted Answer

To invoke a method from the parent class

Answer

To access a protected variable from the parent class

Answer

To instantiate a new object of the parent class

Answer

To cast an object to the parent class

Question 3

Which design pattern is commonly employed to represent a 'has-a' relationship between objects?

Accepted Answer

Composite

Answer

Factory

Answer

Singleton

Answer

Builder

Question 4

Which option is NOT a visibility modifier in Java?

Accepted Answer

internal

Answer

public

Answer

protected

Answer

private

Question 5

What is the primary goal of polymorphism in software design?

Accepted Answer

To enable objects of different classes to respond differently to the same message

Answer

To prevent access to protected members of a class

Answer

To enforce encapsulation of data and methods

Answer

To create objects at runtime

Question 6

Which of the following best describes the 'Open-Closed' principle in software design?

Accepted Answer

Classes should be open for extension but closed for modification.

Answer

Classes should be closed for extension but open for modification.

Answer

Classes should be closed for both extension and modification.

Answer

Classes should be open for both extension and modification.

Question 7

What is the primary objective of encapsulation in object-oriented design?

Accepted Answer

To prevent unauthorized access to an object's internal state, enhancing data integrity and security

Answer

To facilitate direct interaction between objects, simplifying communication

Answer

To enforce the creation of objects in a specific order, ensuring proper system initialization

Answer

To optimize code performance by reducing the number of method calls

Question 8

Which of the following is NOT an advantage of inheritance in object-oriented programming?

Accepted Answer

Increased complexity: Potentially introducing intricate relationships and dependencies between classes

Answer

Code reuse: Leveraging existing code to reduce development time and effort

Answer

Polymorphism: Enabling objects of different types to respond to the same message

Answer

Improved maintainability: Facilitating code updates by modifying the base class, which propagates changes to derived classes

Question 9

In the Model-View-Controller (MVC) architectural pattern, what is the primary responsibility of the controller component?

Accepted Answer

Managing user input, interacting with the model, and updating the view

Answer

Updating the view based on changes in the model

Answer

Storing and manipulating data for the application

Answer

Defining the business logic for the application

Question 10

What is the primary purpose of UML class diagrams?

Accepted Answer

To provide a visual representation of the structure and relationships of classes within a system

Answer

To generate code for the system automatically

Answer

To document the requirements for the system

Answer

To test the functionality of the system

Question 11

Which of the following is considered a best practice for designing classes in object-oriented programming?

Accepted Answer

Creating classes that are small, focused, and cohesive, with a single, well-defined responsibility

Answer

Using public fields to allow easy access to data, simplifying development

Answer

Avoiding inheritance whenever possible, as it can introduce complexity

Answer

Designing classes that lack cohesion, with responsibilities scattered across multiple classes

Question 12

Identify the principle of Object-Oriented Design that does NOT exist?

Accepted Answer

Data Hiding

Answer

Encapsulation

Answer

Inheritance

Answer

Polymorphism

Question 13

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

Accepted Answer

Access the current object

Answer

Invoke the calling method

Answer

Instantiate a new instance of the class

Answer

Transfer data between objects

Question 14

Which visibility modifier in Java allows access to a class member outside its package?

Accepted Answer

public

Answer

protected

Answer

private

Answer

static

Question 15

In Java, what is the primary function of an interface?

Accepted Answer

Establish a contract that classes must adhere to

Answer

Instantiate a class

Answer

Access private members of a class

Answer

Provide a mechanism for method overloading

Question 16

Which design principle dictates that objects should only depend on abstractions, not concrete implementations?

Accepted Answer

Dependency Inversion Principle

Answer

Open-Closed Principle

Answer

Liskov Substitution Principle

Answer

Interface Segregation Principle

Question 17

What is the purpose of constructor overloading?

Accepted Answer

Create objects with different initial states

Answer

Reduce the number of constructors in a class

Answer

Enforce a specific order of initialization

Answer

Allow objects to be passed as parameters

Question 18

Explain the distinction between a class and an object?

Accepted Answer

A class is a template; an object is an instance of that template

Answer

An object is a template; a class is an instance of that template

Answer

A class and an object represent the same concept

Answer

An object can exist independently of a class, but a class cannot exist independently of an object

Question 19

Rewritten Question: Which fundamental principle of Object-Oriented Design is missing from the following list?

Accepted Answer

Aggregation

Answer

Encapsulation

Answer

Inheritance

Answer

Polymorphism

Question 20

Rewritten Question: What is the primary purpose of encapsulation in Object-Oriented Design?

Accepted Answer

To conceal the implementation details of an object, enhancing security and maintainability.

Answer

To improve the readability and organization of the code.

Answer

To increase the performance of the software.

Answer

To restrict access to sensitive data.

Question 21

Rewritten Question: In Object-Oriented Design, which visibility modifier limits access to an attribute or method to only the class where it is defined?

Accepted Answer

private

Answer

public

Answer

protected

Answer

default

Question 22

Rewritten Question: What is the primary advantage offered by inheritance in Object-Oriented Design?

Accepted Answer

Code reusability through the inheritance of common attributes and behaviors.

Answer

Polymorphic behavior, enabling objects to respond differently to the same method call.

Answer

Encapsulation, ensuring data hiding and controlled access.

Answer

Encapsulation and code reusability, combining the benefits of both concepts.

Question 23

Rewritten Question: Which alternative listed below is not a recognized type of polymorphism?

Accepted Answer

Type erasure, a feature in some programming languages where generic type information is removed during compilation.

Answer

Ad-hoc polymorphism, allowing objects of different types to be treated as objects of a common superclass.

Answer

Overloading, involving multiple methods with the same name but different parameters.

Answer

Overriding, occurring when a subclass redefines a method inherited from its superclass.

Question 24

Rewritten Question: What is the role of the Liskov Substitution Principle in Object-Oriented Design?

Accepted Answer

To ensure that derived classes can be used in place of their base classes without altering the program's behavior.

Answer

To prevent the creation of unnecessary classes.

Answer

To enforce encapsulation and restrict access to critical data.

Answer

To improve the readability and understandability of the code.

Question 25

Rewritten Question: What is the main purpose of a UML class diagram in software design?

Accepted Answer

To visually represent the structure and relationships within a software system.

Answer

To automatically generate code based on the diagram.

Answer

To document the functional requirements of the system.

Answer

To test the system's functionality and identify errors.

Question 26

Rewritten Question: Which software development methodology is considered the most suitable for Object-Oriented Design?

Accepted Answer

Agile, an iterative and incremental approach.

Answer

Waterfall, a sequential and structured approach.

Answer

Iterative, a repetitive process involving design, implementation, and testing.

Answer

Spiral, a risk-driven approach that iterates through development phases.

Question 27

In object-oriented analysis, what is the distinction between use case diagrams and class diagrams?

Accepted Answer

Use case diagrams show user-system interactions, while class diagrams depict system architecture.

Answer

Class diagrams show user-system interactions, while use case diagrams depict system architecture.

Answer

Both use case diagrams and class diagrams show user-system interactions.

Answer

Both use case diagrams and class diagrams depict system architecture.

Question 28

What is the primary purpose of encapsulation in OOD?

Accepted Answer

To conceal implementation details and protect data integrity

Answer

To enable code reuse and improve maintainability

Answer

To define the behavior of objects

Answer

To prevent unauthorized access to data

Question 29

What is the primary purpose of a class diagram in OOD?

Accepted Answer

To visually represent the structure and relationships of a system

Answer

To define the attributes and operations of objects

Answer

To specify the flow of control in a system

Answer

To automatically generate code

Question 30

What is the objective of the SOLID principles in OOD?

Accepted Answer

To guide the design of flexible, maintainable, and reusable classes and interfaces

Answer

To enforce specific coding conventions and styles

Answer

To improve code performance and efficiency

Answer

To facilitate automatic code generation

Question 31

What is the fundamental difference between a class and an object in OOD?

Accepted Answer

A class is a blueprint or template, while an object is a specific instance of that class

Answer

A class is a collection of objects, while an object is a single entity

Answer

A class defines behavior, while an object stores data

Answer

There is no distinction between a class and an object

Question 32

When is the 'Singleton' design pattern typically used?

Accepted Answer

To ensure only one instance of a resource or service exists in an application

Answer

To make objects immutable throughout the application

Answer

To lazily initialize objects, creating them only when needed

Answer

To encapsulate complex business logic in a single unit

Question 33

In object-oriented software development, what is the purpose of 'Refactoring' and what are its key benefits?

Accepted Answer

Refactoring involves restructuring code while preserving its functionality.

Answer

Refactoring only makes superficial code changes without altering functionality.

Answer

Refactoring is an optional practice with minimal impact on software development.

Answer

Refactoring is only useful in the early stages of development and cannot be applied to existing code.

Question 34

Which of the following is NOT a fundamental principle of Object-Oriented Design (OOD)?

Accepted Answer

Aggregation

Answer

Encapsulation

Answer

Inheritance

Answer

Polymorphism

Question 35

Which of the following best describes the purpose of encapsulation in OOD?

Accepted Answer

Hiding implementation details from users while providing a well-defined interface

Answer

Enforcing data integrity through access control

Answer

Promoting code reusability by allowing classes to inherit from each other

Answer

Simplifying object creation by automating the process

Question 36

What is the relationship between a derived class and its base class?

Accepted Answer

Is-a

Answer

Has-a

Answer

Part-of

Answer

Uses-a

Question 37

Which of the following is a key benefit of polymorphism in OOD?

Accepted Answer

Reduced coupling between classes by allowing objects to interact through a common interface

Answer

Improved code readability by eliminating the need for type checking

Answer

Increased code maintainability by making it easier to modify and extend code

Answer

Enhanced runtime performance by optimizing code execution based on object types

Question 38

In object-oriented design, what is a key advantage of using code contracts?

Accepted Answer

Increased software reliability

Answer

Enhanced code readability

Answer

Reduced development time

Question 39

What is the main purpose of using private access modifiers in object-oriented programming?

Accepted Answer

To restrict access to data and methods within a class, enhancing data integrity and encapsulation

Answer

To allow access to data and methods from anywhere in the program, promoting code reusability

Answer

To protect sensitive data from unauthorized access, improving security

Answer

To improve the efficiency of the program by reducing the scope of variables

Question 40

Which of the following is NOT a benefit of polymorphism in software design?

Accepted Answer

Enhanced runtime performance by optimizing code execution based on specific object types

Answer

Increased code flexibility by allowing objects to respond differently to the same method call

Answer

Reduced code redundancy by eliminating the need for multiple implementations of similar functionality

Answer

Improved code maintainability by making it easier to modify and extend code

Question 41

Consider a base class Shape and a derived class Rectangle. Which of the following relationships best describes the inheritance between these classes?

Accepted Answer

Is-a

Answer

Has-a

Answer

Can-do

Answer

Is-like

Question 42

Which design pattern is commonly used to provide a consistent interface for interacting with different types of objects?

Accepted Answer

Abstract factory

Answer

Factory method

Answer

Builder

Answer

Strategy

Question 43

What is the primary purpose of the @Override annotation in Java?

Accepted Answer

To indicate that a method in a subclass overrides a method in its superclass.

Answer

To prevent a subclass from overriding a method in its superclass.

Answer

To make a method private in a subclass.

Answer

To throw an exception if a method is not implemented in a subclass.

Question 44

Which of the following is a core principle of Object-Oriented Design?

Accepted Answer

Encapsulation: Bundling data and methods that operate on that data into a single unit.

Answer

Algorithmic efficiency: Optimizing software code for performance.

Answer

Code reusability: Designing software components that can be reused in multiple contexts.

Answer

Procedural programming: Breaking down a problem into a series of sequential steps.

Question 45

Which of the following accurately describes inheritance?

Accepted Answer

It allows derived classes to inherit properties and methods from base classes.

Answer

It is a form of code duplication.

Answer

It always leads to better code performance.

Question 46

Which of the following is an advantage of using interfaces?

Accepted Answer

They promote loose coupling between classes, making them more flexible and maintainable.

Answer

They improve code readability.

Answer

They guarantee that all implementing classes have the same methods.

Answer

They always lead to better code performance.

Question 47

What is the primary function of a design pattern?

Accepted Answer

To provide a proven solution to a common software design problem, making code more reusable and maintainable.

Answer

To enforce coding standards.

Answer

To improve code readability.

Question 48

What is the fundamental difference between a class and an object?

Accepted Answer

A class is a template or blueprint, defining the structure and behavior of objects, while an object is an instance of a class, containing specific data and exhibiting the behavior defined by the class.

Answer

A class is static, while an object is dynamic.

Answer

A class has methods, while an object has data.

Question 49

What is the significance of association in OOD?

Accepted Answer

It models relationships and connections between objects, allowing them to interact and collaborate.

Answer

It ensures that all objects are connected.

Answer

It prevents code duplication.

Answer

It improves code readability.

Question 50

Which of the following is a characteristic of a well-designed class?

Accepted Answer

It has high cohesion and low coupling.

Answer

It is difficult to understand.

Answer

It is not reusable.

Answer

It has a large number of methods.

Question 51

What is the purpose of a UML class diagram?

Accepted Answer

To visually represent the structure and relationships of classes in a system.

Answer

To generate code automatically.

Answer

To document design decisions.

Question 52

Which of the following is a best practice for OOD?

Accepted Answer

Favor composition over inheritance.

Answer

Avoid using interfaces.

Answer

Inherit from as many base classes as possible.

Answer

Create classes with many methods.