The SOLID Design Principles 👨‍🎓

Table Of Contents

• Single Responsibility Principle
• Open/Closed Design Principle
• Liskov Substitution Principle
• Interface Segregation Principle
• Dependency Inversion Principle

Single Responsibility Principle

• Each class should be responsible for a single part or functionality of the system.

public class Entity {
    public void printTooMuchDetails() {}
    public void calculateEstimate() {}
    public void addEntityToDatabase() {}
}

The Entity class has three separate responsibilities: reporting, calculation, and database. This violate the SRP principle.

A better approach would be to separate the above class into three classes with separate responsibilities.

Open/Closed Design Principle

Liskov Substitution Principle

Interface Segregation Principle

Dependency Inversion Principle