1 / 19

Use Cases -Use Case Diagram

Use Cases -Use Case Diagram . Chapter 3. Where are we?. Outline. Use Case – defined Techniques for Identifying Use Cases User Goal Even Decomposition CRUD Analysis UML's Use Case Diagram . Use Case - Defined. Use case - an activity that the system performs

ernie
Télécharger la présentation

Use Cases -Use Case Diagram

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Use Cases-Use Case Diagram Chapter 3

  2. Where are we?

  3. Outline • Use Case – defined • Techniques for Identifying Use Cases • User Goal • Even Decomposition • CRUD Analysis • UML's Use Case Diagram

  4. Use Case - Defined • Use case - an activity that the system performs • usually in response to a request by a user • Functional Requirements • Verb + Noun • Place order • Issue complaint

  5. Identifying Use Cases • 3 Techniques • User Goal • Event Decomposition • CRUD Analysis

  6. Identifying Use Cases- User Goal Technique • Ask the users what they needthe system to do • Identify the users • Interview them • Create the list of use cases • Watch out for duplicates, inconsistencies • Some users may need the same use case • Verify the list with the users

  7. Identifying Use Cases- Event Decomposition • Identify the eventsthat occur to which the system must respond. • Event - an occurrence at a specific time & place which needs to be remembered • Use Case - what the system does when the event occurs Prior Conditions & Events

  8. Identifying Use Cases- Event Decomposition • Types of Events • External • Temporal • State

  9. Identifying Use Cases- Event Decomposition • Transaction's Life Cycle • System Controls • These events are dealt with in the Design Phase • Log in, time to change password, change user preferences, backup the DB, recover a DB • "Perfect technology Assumption"

  10. Identifying Use Cases- Event Decomposition • Naming use cases based on events

  11. Identifying Use Cases - CRUD Analysis • Can be a tool for: use case identification and/or validation • Ensure that there are use cases to cover the CRUD CRUD - For 1 data entity C R U D • CRUD Matrix • All use cases • All data entities • Shows responsibilities

  12. CRUD CRUD Use Cases Cancel order Place order Change order Print order report View order status Update customer profile … CRUD Matrix

  13. UML'sUse Case Diagram

  14. UML - The Unified Modeling Language • An Object-Oriented modeling language • "3 Amigos" - Booch, Rumbaugh, and Jacobson • Adopted & now managed by OMG (Object Management Group) • Models both structure & behavior • Structure diagrams • Class diagram, Component diagram, Deployment diagram, Object diagram, Package diagram, etc. • Behavior diagrams • Activity diagram , Use Case diagram , Sequence diagram, State machine, Communication diagram, etc. 14

  15. Use Case Diagram • A UML diagram depicting the relationship between actors & use cases • Defines Scope/Functional Requirements • Automation Boundary • The boundary between the software and the actors of the system • Actor • Anyone or thing that interacts with the system • Use Case • an activity that the system performs • Association • Depicts a usage relationship between an actor and a use case • <<includes>> Relationship • Used when one use case (base) includes another use case (the inclusion use case) Billing <<system>> Customer Time <<includes>>

  16. Use Case Diagram - Example • Prefer "Place an order"

  17. Use Case Diagram - Example • Prefer "Place an order" Create new order <<includes>> <<includes>> Lookup item availability Customer Validate customer account Sales clerk <<includes>> <<includes>> Update order

  18. Use Case Diagram - Practice ATM System Withdraw cash Customer

  19. "Withdraw Cash” Use Case – i.e. scenario Withdraw cash Customer Customer ATM Bank

More Related