Detailed Explanation of Single Responsibility

Single Responsibility Principle (SRP)

Detailed Explanation

How it Applies in Object-Oriented Design In object-oriented design, SRP ensures that a class has only one responsibility. This means a class should encapsulate all the functionality related to a single concept or purpose. When changes are required, they should affect only the classes directly associated with that specific responsibility, leading to fewer side effects and more predictable code behavior.

Key Concepts and Terminology

• Responsibility: The reason for a class to change. Each responsibility is an axis of change, meaning a class should only be concerned with one particular aspect of the application.
• Cohesion: The degree to which the elements of a class belong together. High cohesion within a class is a sign of SRP adherence.
• Separation of Concerns: Dividing a program into distinct sections, each addressing a separate concern or functionality. SRP is a fundamental practice for achieving separation of concerns.

Do’s and Don’ts

• Do:

  • Ensure each class has a single responsibility.
  • Group related functions that change for the same reasons together.
  • Refactor classes that have multiple responsibilities into smaller, more focused classes.

• Don’t:

  • Cram multiple unrelated functionalities into a single class.
  • Allow a class to become a “God object” with too many responsibilities.
  • Ignore high coupling resulting from a class handling multiple responsibilities, making changes more difficult and error-prone.