B CompE Bachelor of Computer Engineering Bachelor of Computer Engineering Object Oriented Programming 2

Question 1

Which design principle states that a class should have only one reason to change?

Accepted Answer

Single Responsibility Principle

Answer

The Single Responsibility Principle (SRP) dictates that each class should encapsulate only one concern so changes to one responsibility don't affect others.

Question 2

In Java, what does the 'super' keyword do when used in a constructor?

Accepted Answer

Calls the parent class constructor

Answer

'super()' in a constructor explicitly invokes the parent class's constructor and must be the first statement in the subclass constructor.

Question 3

Which UML relationship represents an 'is-a' association between classes?

Accepted Answer

Generalization

Answer

Generalization (shown as a solid line with a hollow arrowhead) models inheritance, expressing that a subclass 'is-a' type of the superclass.

Question 4

What is the output of calling a virtual method through a base class pointer pointing to a derived object in C++?

Accepted Answer

Derived class version is called

Answer

Virtual dispatch ensures the most-derived override is called at runtime, which is the core mechanism of polymorphism in C++.

Question 5

What is the purpose of an abstract class in OOP?

Accepted Answer

To prevent any instantiation and force subclasses to implement certain methods

Answer

Abstract classes serve as templates; they may contain abstract methods that concrete subclasses must implement, and cannot be instantiated directly.

B CompE Bachelor of Computer Engineering Practice Test

B CompE Bachelor of Computer Engineering Practice Test

B CompE Bachelor of Computer Engineering Bachelor of Computer Engineering Object Oriented Programming 2