Single Responsibility Principle

Single-purpose methods produce minimal focused signatures and clear testable roles. Applying SRP systematically helps prevent Feature Envy from reappearing. The polymorphic approach of one subclass per type adheres to the Single Responsibility Principle. The Single Responsibility Principle says each class should have exactly one reason to change. The Single Responsibility Principle states that a class should have only one reason to change, meaning it is responsible for exactly one job or concern. Breaking a bloated method into smaller single-purpose methods is recommended. The Single Responsibility Principle is the refactoring principle applied to Feature Envy. The Single Responsibility Principle requires each class to manage exactly one type of behavior. A UserProfile class that manages user data, sends email notifications, and handles data persistence violates SRP because it has multiple reasons to change. Replacing an email provider requires modifying the UserProfile class when SRP is violated, which risks breaking unrelated user data logic. The fix for the SRP violation is splitting UserProfile into two focused classes: UserProfile for user data and EmailService for email noti…