Скачать или смотреть Mastering SOLID Principles in 1 Minute

Mastering SOLID Principles in 1 Minute
S – Single Responsibility Principle (SRP)
Definition: A class should have only one reason to change.
Meaning: Each class should focus on a single task or responsibility. This keeps the code modular and easier to maintain.
Example: A UserManager class should handle user-related logic, not also handle email notifications.
O – Open/Closed Principle (OCP)
Definition: Software entities should be open for extension but closed for modification.
Meaning: You should be able to add new functionality without changing the existing code.
Example: Use inheritance or interfaces to add new features instead of modifying existing classes.
L – Liskov Substitution Principle (LSP)
Definition: Objects of a superclass should be replaceable with objects of a subclass without affecting the functionality.
Meaning: A subclass should be able to stand in for its parent class without causing issues.
Example: If a class Bird has a method fly(), a subclass Penguin should not inherit it if penguins cannot fly. This breaks LSP.
I – Interface Segregation Principle (ISP)
Definition: A class should not be forced to implement interfaces it doesn’t use.
Meaning: Instead of one large interface, create smaller, more specific ones.
Example: Instead of a Vehicle interface with drive() and fly() methods, create separate Car and Plane interfaces.
D – Dependency Inversion Principle (DIP)
Definition: High-level modules should not depend on low-level modules. Both should depend on abstractions.
Meaning: Code should depend on interfaces or abstract classes, not concrete implementations.
Example: Instead of a DatabaseManager class directly using a MySQLDatabase, it should depend on a Database interface that can work with any database type.