Software Design Principles PDF

Software Design Principles Ensuring Scalable, Maintainable, and Flexible Software Introduction Today, we’ll dive into core principles that guide good software design. Objectives: - Understand the importance of design principles. - Learn key principles like modularity, DRY, and SOLID. - Apply t...

Software Design Principles Ensuring Scalable, Maintainable, and Flexible Software Introduction Today, we’ll dive into core principles that guide good software design. Objectives: - Understand the importance of design principles. - Learn key principles like modularity, DRY, and SOLID. - Apply these principles to real-world scenarios. Importance of Software Design Principles Software adhering to design principles is: - Easier to test and debug. - Flexible to change. - Resilient to breaking when new features are added. Real-World Example: - A poorly designed e-commerce website Fundamental Design Principles 1. Modularity: Breaking a system into smaller, independent parts. 2. DRY (Don’t Repeat Yourself): Avoid duplicating code. 3. KISS (Keep It Simple, Stupid): Simplify design to avoid overengineering. Fundamental Design Principles Refactor Poor Design Refactor Poor Design SOLID Principles Overview 1. SRP: Single Responsibility Principle 2. OCP: Open/Closed Principle 3. LSP: Liskov Substitution Principle 4. ISP: Interface Segregation Principle 5. DIP: Dependency Inversion Principle SRP: Single Responsibility Principle OCP: Open/Closed Principle LSP: Liskov Substitution Principle ISP: Interface Segregation Principle DIP: Dependency Inversion Principle Common Design Trade-Offs Modularity vs. Performance: Modular code may have higher overhead. Flexibility vs. Complexity: Extensible code can introduce complexity. Reusability vs. Deadlines: Reusable components take longer to develop. Case Study: Task Management App Scenario: Create tasks with deadlines. Categorize tasks as Personal or Work. Send reminders for overdue tasks. Solution: Task Management App Single Responsibility Principle: Separate task creation and reminder logic into different classes. Open/Closed Principle: Allow adding new task categories (e.g., Health) Dependency Inversion Principle: Use an abstraction layer for sending reminders to support both email and SMS. Single Responsibility Principle (SRP) Open/Closed Principle (OCP) Dependency Inversion Principle (DIP) Trade-Offs and Final Design Wrap-Up and Q&A Design principles ensure scalable, maintainable, and flexible software. Focus on modularity, DRY, KISS, and SOLID principles. How can you apply these principles to your next programming project?