Why requirements modeling?
To better understanding requirements and relationship to a system
Communicating desired structure and behaviour of our system to guide development
Uncover hidden problems
Requirements analysis model
A model is an abstract representation of existing reality or reality to be created
Requirements models perspectives
Types of scenarios
As-is scenario
Used in describing a current situation.
Visionary scenario
Used to describe a future system. Usually described in greenfield engineering or reengineering.
Evaluation scenario
Used to compare alternative solutions.
Use cases
Use cases are used to document the functionalities of planned or existing system on basis of simple models
Concepts
Use case diagrams
Use case specifications
Use case: From warehouse on fire to report emergency
Why Use Case Diagrams?
Organizing functional requirements in system and user interaction with system
Identify interrelationships between requirements
Easy to understand
Modellinh elements of use case diagrams
Why object modeling?
Main goal: Find the important abstractions
Question: What happens if we find wrong abstractions?
Anwer: We iterate and revise the model.
Modelling element of object (class) diagrams (UML)
Different types of classes
Entity classes
Represent the persistent information tracked by the system
Boundary classes
interaction between the user and the system
Control classes
control tasks to be performed by the system
Last changed5 months ago