IKM Object-Oriented Programming Principles 2

Question 1

What is encapsulation in OOP?

Accepted Answer

Bundling data and methods while restricting access to internal state

Answer

Inheriting methods

Answer

Creating multiple objects

Answer

Using interfaces

Question 2

What is the difference between overloading and overriding?

Accepted Answer

Overloading uses different parameters in same class; overriding redefines a parent method in subclass

Answer

Overloading changes return types

Answer

They are the same

Answer

Overloading is compile-time only

Question 3

What is an abstract class?

Accepted Answer

Class that cannot be instantiated and may contain abstract methods

Answer

Class with no methods

Answer

Class with only static methods

Answer

Class that auto garbage collects

Question 4

What is the Liskov Substitution Principle?

Accepted Answer

Subclass objects should be replaceable for superclass objects without breaking the program

Answer

Single responsibility

Answer

Depend on abstractions

Answer

Open for extension

Question 5

What is composition over inheritance?

Accepted Answer

Favoring has-a relationships over is-a relationships for code reuse

Answer

Using constructors over factories

Answer

Composing interfaces

Answer

Multiple inheritance

Question 6

What is the purpose of an interface in OOP?

Accepted Answer

Define a contract of methods implementing classes must provide

Answer

Store global variables

Answer

Manage memory

Answer

Handle logging