Software Engineering Principles

• Software engineering is the process of designing, developing, testing, and maintaining software applications using engineering principles.

Design Principles

• Abstraction focuses on essential details while ignoring unnecessary ones.
• Decomposition involves breaking down large problems into smaller, manageable parts.
• Control flow-based design focuses on the order in which instructions are executed.
• Structured programming organizes code into clear, readable sections.
• Data structure-oriented design focuses on how data is stored and managed.
• Data flow-oriented design focuses on how data moves through a system to structure logic.
• Object-oriented design models programs using real-world objects with data and behavior.

Qualities of Software Engineering Products

• Delivered on time and within budget
• Functional to specifications
• User-friendly
• Error-free
• Flexible and adaptable

McCall's Quality Factors

• Efficiency, integrity, reliability, usability, accuracy
• Maintainability, testability, flexibility, interface facility
• Re-usability, transferability

Application Dimensions

• Characteristics, responsiveness, and type

Waterfall Model

• A step-by-step software development process requires completion of each phase, like planning, design, coding, and testing, before moving to the next.
• Iterative waterfall model revisits earlier phases for modifications before finalizing the project.
• The V-Model is a development model where each stage has a corresponding testing phase, forming a "V" shape for quality assurance.
• Prototyping creates a rough software version to gather feedback before the final product.

Integrated Development Environments (IDEs)

• IDEs help developers write and test code easily (e.g., Eclipse, PyCharm, VS Code).
• Version control tracks and manages code changes over time.
• Project management tools manage tasks, timelines, and budgets for software projects. (e.g., Jira, ClickUp).
• Software testing tools find software bugs and ensure quality (e.g., Spiratest, Selenium).
• Build automation tools convert source code into ready-to-use software automatically (e.g., Maven).
• Collaboration tools help teams communicate and work together efficiently.
• Design and modeling tools visualize and plan software structures and workflows.
• Database management tools create, store, and manage databases (e.g., MySQL, MongoDB).
• Deployment tools automate launching software in different environments (e.g., Docker, Ansible).

Software Design Objectives

• Correctness, completeness, efficiency, flexibility, consistency, and maintainability
• Software design involves planning and structuring software for efficiency, maintainability, and meeting user requirements.
• Problem partitioning breaks large problems into smaller, manageable parts.
• Abstraction hides complex details to focus on essential features.
• Modularity divides a program into independent, reusable modules.
• Top-down design starts from the main structure to the details.
• Bottom-up design combines small components into a full system.
• Code refactoring improves existing code without changing its functionality, making it cleaner, more efficient, and easier to maintain.
• Software integration combines different software components/systems to work together.
• Software deployment releases and sets up software for users/systems, including installation and updates.

Diagrams in Software Design

• Activity diagrams display the sequence of activities in a step-by-step process.
• Data flow diagrams (DFD) visually represent data flow in a system, showing processes that transfer data from input to storage and report generation.
• Use case diagrams show how users interact with a system and its features.
• Entity-relationship diagrams (ERD) represent the relationships between data in a database.
• Database normalization organizes a database to reduce redundancy and improve efficiency.
• Data dictionaries list, define, and describe data elements in a system.
• System architecture includes components and their interactions.
• The process of organizing a database to remove duplicate data and avoid errors is called database normalization.
• A document that describes data types, formats, and relationships in a system is called data dictionary.
• The overall structure of a system including its hardware, software, and network setup, is the system architecture.