Practical Guide to Apply OOP Principles

Object-oriented programing

• Useful for:
  • high maintananciblity
  • Role devision

	Explanation	Example
encapsulation	Restrict external access to protect internal data	access modifiers
abstruction	Extract significant features and encapsulate the details	abstract class, interface
inheritance	Inherit features from base class	base class, sub class
polymorphism	Integrate interface between among classes	Override methods, Overload methods

SOLID Principle

	Name	Explanation
S	Single Responsibility	a class should have sole responsibility
O	Open Closed	open to extend, close to modify
L	Liskov Substitution	Sub class should be compatible with its Base class
I	Interface Segregation Principle	Many client-specific interfaces are better than one general-purpose interface
D	Dependency Inversion	High-level modules should not import anything from low-level modules

How to apply

Phase	Principle
Requirements Definition	Single Responsibility
Design	Intrface Segregation
Coding	Liscov Substitution, Dependency Inversion
Enhance	Open Closed