Requirements Engineering Fundamentals

Requirements Engineering

• Definition: The process of defining, documenting, and maintaining requirements
• Importance: Ensures that the software meets the user's needs and expectations
• Activities:
  • Elicitation: Gathering requirements through stakeholder interviews, surveys, and observations
  • Analysis: Breaking down high-level requirements into more detailed and specific ones
  • Specification: Documenting requirements in a clear and concise manner
  • Validation: Ensuring that the requirements are correct and complete
  • Management: Tracking changes and updates to requirements throughout the project
• Types of Requirements:
  • Functional: Describe what the system must do
  • Non-Functional: Describe how the system should perform (e.g. security, performance)

Testing Strategies

• Types of Testing:
  • Unit Testing: Testing individual units of code to ensure they function correctly
  • Integration Testing: Testing how units of code work together
  • System Testing: Testing the entire system to ensure it meets requirements
  • Acceptance Testing: Testing to ensure the system meets user acceptance criteria
• Testing Levels:
  • Black Box Testing: Testing based on input and output without knowledge of internal workings
  • White Box Testing: Testing with knowledge of internal workings
  • Gray Box Testing: Combination of black box and white box testing
• Testing Techniques:
  • Equivalence Partitioning: Dividing input data into partitions and testing each
  • Boundary Value Analysis: Testing at the boundaries of input data
  • State Transition Testing: Testing the system's behavior in different states

Agile Development

• Core Values:
  • Individuals and Interactions: People and communication are more important than processes and tools
  • Working Software: Working software is more important than comprehensive documentation
  • Customer Collaboration: Collaboration with customers is more important than contract negotiation
  • Responding to Change: Responding to change is more important than following a plan
• Agile Methodologies:
  • Scrum: Framework for managing and completing complex projects
  • Kanban: Visual system for managing work, emphasizing continuous flow
  • Extreme Programming (XP): Iterative approach to software development
• Agile Practices:
  • Iteration: Breaking down work into smaller, manageable chunks
  • Sprint: Time-boxed iteration, usually 1-4 weeks
  • Daily Stand-up: Daily meeting to discuss progress and plans
  • Retrospective: Reviewing the iteration to identify improvements

Requirements Engineering

• Requirements engineering is the process of defining, documenting, and maintaining requirements to ensure software meets user needs and expectations
• Importance of requirements engineering: ensures software meets user needs and expectations

Requirements Engineering Activities

• Elicitation: gathering requirements through stakeholder interviews, surveys, and observations
• Analysis: breaking down high-level requirements into detailed and specific ones
• Specification: documenting requirements clearly and concisely
• Validation: ensuring requirements are correct and complete
• Management: tracking changes and updates to requirements throughout the project

Types of Requirements

• Functional requirements: describe what the system must do
• Non-functional requirements: describe how the system should perform (e.g. security, performance)

Testing Strategies

Types of Testing

• Unit testing: testing individual units of code to ensure they function correctly
• Integration testing: testing how units of code work together
• System testing: testing the entire system to ensure it meets requirements
• Acceptance testing: testing to ensure the system meets user acceptance criteria

Testing Levels

• Black box testing: testing based on input and output without knowledge of internal workings
• White box testing: testing with knowledge of internal workings
• Gray box testing: combination of black box and white box testing

Testing Techniques

• Equivalence partitioning: dividing input data into partitions and testing each
• Boundary value analysis: testing at the boundaries of input data
• State transition testing: testing the system's behavior in different states

Agile Development

Agile Core Values

• Individuals and interactions: people and communication are more important than processes and tools
• Working software: working software is more important than comprehensive documentation
• Customer collaboration: collaboration with customers is more important than contract negotiation
• Responding to change: responding to change is more important than following a plan

Agile Methodologies

• Scrum: framework for managing and completing complex projects
• Kanban: visual system for managing work, emphasizing continuous flow
• Extreme programming (XP): iterative approach to software development

Agile Practices

• Iteration: breaking down work into smaller, manageable chunks
• Sprint: time-boxed iteration, usually 1-4 weeks
• Daily stand-up: daily meeting to discuss progress and plans
• Retrospective: reviewing the iteration to identify improvements

Testing Strategies

Black Box Testing

• Tests software without knowledge of internal workings
• Focuses on inputs and expected outputs
• Advantages:
• Simple and easy to use
• Fast test development
• Tests are not dependent on implementation details
• Disadvantages:
• May not cover all possible scenarios
• Difficult to achieve high coverage

White Box Testing

• Tests software with knowledge of internal workings
• Focuses on internal structure and implementation
• Advantages:
• High coverage possible
• Can detect hidden errors
• Optimizes testing efforts
• Disadvantages:
• Requires detailed knowledge of software
• Time-consuming and expensive
• May be difficult to maintain

Gray Box Testing

• Combines black box and white box testing
• Tests software with some knowledge of internal workings
• Advantages:
• Balances advantages of black and white box testing
• More efficient than white box testing
• More effective than black box testing
• Disadvantages:
• Requires some knowledge of software
• May not be as effective as white box testing

Integration Testing

• Tests integrated modules to ensure correct interactions
• Types:
• Big Bang Integration: Integrates all modules at once
• Top-Down Integration: Integrates from highest level to lowest level
• Bottom-Up Integration: Integrates from lowest level to highest level
• Sandwich Integration: Combines top-down and bottom-up integration
• Advantages:
• Ensures correct interactions between modules
• Detects errors early
• Disadvantages:
• Requires careful planning and execution
• May be time-consuming and expensive

Unit Testing

• Tests individual modules or units of code
• Focuses on ensuring each unit functions correctly
• Advantages:
• Fast and inexpensive
• Early detection of errors
• Improves code quality
• Disadvantages:
• Does not ensure correct interactions between units
• May not detect integration errors

Learn about the process of defining, documenting, and maintaining requirements in software development, including elicitation, analysis, specification, and validation activities.