This document discusses the principles of object-oriented programming (OOP). It outlines the four major OOP principles: data abstraction, encapsulation, inheritance, and polymorphism. Data abstraction involves modeling real-world objects, encapsulation keeps data and functions together, inheritance allows child classes to inherit attributes and behaviors from parent classes, and polymorphism allows classes to share a common interface but have different implementations. The document also lists the five major design principles for OOP: single responsibility, open/closed, Liskov substitution, interface segregation, and dependency inversion. It provides examples to illustrate inheritance, polymorphism, and the Liskov substitution principle in the context of eating hamburgers and drinking beverages.

1. OOP Principles
I like a hamburger!

2. OOP?
Something to eat?

3. OOP
Object-Oriented Programming
OBJECT
OBJECT
OBJECT
OBJECT
OBJECT

4. OOP
Object-Oriented Programming
OBJECTs
...
... ...

5. What is the “Principles”?
● Guidelines for the best way!
● Use to define a word!
● Prevent to mistake!
● etc.

6. Principles for OOP
4 Major Principles for OOP
5 Major Design Principles for OOP
S. O. L. I. D
Data Abstraction Encapsulation
Inheritance Polymorphism

7. 4 Major Principles for OOP
Data Abstraction
Hamburgers Beverage
FOOD

8. 4 Major Principles for OOP
Encapsulation
Just eat!
Call eat action!

9. 4 Major Principles for OOP
Inheritance
Parent
Child Child

10. 4 Major Principles for OOP
Polymorphism
[Eat] eat(void)
[Eat] eat(withBeverage)
[Eat] eat(withSnack)
Just eat!
Call eat action!
But
[Eat] …….

11. 5 Major Design Principles for OOP
SRP (Single Responsibility Principle)SETSET
But !!
I want to drink a orange juice!

12. Straw
5 Major Design Principles for OOP
OCP (Open Closed Principle)
Opened
Closed

13. 5 Major Design Principles for OOP
LSP (Liskov Substitution Principle)
We can eat all hamburgers
because contains "Eater Action"!
And all action is true!
Just eat!!!
eat
eat eat

14. 5 Major Design Principles for OOP
ISP (Interface Segregation Principle)
DRINK + EAT
DRINK
EAT
Not bad!

15. 5 Major Design Principles for OOP
DIP (Dependency Inversion Principle)

16. Q / A

17. Thanks to
- MCDoxxld in America
- BHX in Korea