Fundamentals / Principles

Question 1

CS Fundamentals

What are the principles in the SOLID acronym?

Answer 1

Single responsibility
Open-closed
Liskov substitution
Interface segregation
Dependency inversion

Question 2

CS Fundamentals

Define (SRP) Single responsibility principle

Answer 2

Software entities should have only a single responsibility.
i.e. only one potential change in the software’s specification should be able to affect the specification of the class.

MOST IMPORTANT!

Question 3

CS Fundamentals

Define (OCP) Open/closed principle

Answer 3

Software entities should be open for extension, but closed for modification.

Question 4

CS Fundamentals

Define (LSP) Liskov substitution principle

Answer 4

Objects in a program should be replaceable with instances of their subtypes without altering the correctness of that program.

Question 5

CS Fundamentals

Define (ISP) Interface segregation principle

Answer 5

Many client-specific interfaces are better than one general-purpose interface.

Question 6

CS Fundamentals

Define (DIP) Dependency inversion principle

Answer 6

Depend upon Abstractions. Do not depend upon concretions.

Think: Dependency injection (DI)