UML Diagrams: Sequence Diagrams The Requirements Model, and The Dynamic Analysis Model

1. UML Diagrams:Sequence DiagramsThe Requirements Model, andThe Dynamic Analysis Model Instructor: Dr. Hany H. Ammar Dept. of Computer Science and Electrical Engineering, WVU

2. Outline • Review of previous Lecture • The Requirements Model and the Analysis model • Importance of Sequence Diagrams • Rules of sequence diagrams • Use Cases and Sequence Diagrams • The System Sequence Diagrams • The Sound Recorder Example • The E-Commerce Example • Other Examples

3. Review of Previous lecture • Review of development phases and UML Development - Overview • Introduction and importance of Use Case Diagrams • Use Case Diagram Rules • Examples of Use Case diagrams • Requirements Elicitation Process • Identify Actors • Identify Scenarios • Identify Use Cases • Refine Use Cases • Identify Relationships between actors and Use Cases • Identify Initial Analysis Objects • Identify Non-functional requirements

4. Requirements, Use cases, and Scenarios

5. SCENARIOS ACTORS USE CASES UML Development - Overview REQUIREMENTS ELICITATION Time D Requirements Engineering System/Object SEQUENCE DIAG. A T A ANALYSIS CLASS DIAGRAM(S) StateChart DIAGRAMs ANALYSIS Specify Domain Objects D I OPERATION CONTRACTS C T Architectural Design Include Design Objects I SUBSYSTEM CLASS/ OR COMPONENT DIAGRAMS DESIGN SEQUENCE DIAG. DEPLOYMENT DIAGRAM O N DESIGN DIAGRAMS A R Detailed DESIGN Y Object Design IMPLEMENTATION CHOICES IMPLEMENTATION Activity DIAGRAMS IMPLEMENTATION PROGRAM

6. Where are we in the Requirements Engineering ? • Requirements Engineering focus: elicitation and analysis

7. The Requirements Model and the Analysis Model The Requirements Elicitation Process Functional/ Nonfunctional Requirements Use Case Diagrams/ Sequence Diagrams (the system level) The Object-Oriented Analysis Process Static Analysis Dynamic Analysis - Class Diagrams - State Diagrams/ Refined Sequence Diagrams (The object level)

8. Outline • The Requirements Model and the Analysis model • Introduction to Requirements Engineering • Importance of Sequence Diagrams • Rules of sequence diagrams • Use Cases and Sequence Diagrams • The System Sequence Diagrams • The Sound Recorder Example • The E-Commerce Example • Other Examples

9. Importance of Sequence Diagrams • Depict object interactions in a given scenario identified for a given Use Case • Specify the messages passed between objects using horizontal arrows including messages to/from external actors • Time increases from Top to bottom

10. Rules of Sequence Diagrams • Sequence Initiation

11. Rules of Sequence Diagrams • Identify objects needed to support use cases, determine sequence of internal events following the external initiating event • Diagrams that are not initiated with an external actor represent only a partial sequence • Partial sequence diagrams should clearly identify the actor initiated sequence diagrams from which they are launched

12. Example of Sequence Diagrams Notation

13. Rules of Sequence Diagrams • Messages specified on interactions can be synchronous or asynchronous Synchronous call

14. Rules of Sequence Diagrams Asynchronous call

15. Rules of Sequence Diagrams • Display operation names on call arrows

16. Rules of Sequence Diagrams Compound and Simple Iteration

17.  Numbering the Sequence of Interactions

18. ‘included’ sequence diagrams

19. Showing alternate behavior in a sequence diagram

20. Showing Extension Point

22. Rules of Sequence DiagramsShowing alternate behavior in a sequence diagram

25. Communication/Collaboration Diagrams They Specify similar information of interactions without the time axis

26. Specifying Timing Requirements

28. Specifying Timing Requirements

29. Specifying Timing Requirements (Data rates in notes)

30. Specifying Timing Requirements: on interactions

31. Specifying Timing Requirements (ave and max)

32. Specifying Timing Requirements: (Timeout events)

33. Outline • The Requirements Model and the Analysis model • Introduction to Requirements Engineering • Importance of Sequence Diagrams • Rules of sequence diagrams • Use Cases and Sequence Diagrams • The System Sequence Diagrams • The Sound Recorder Example • The E-Commerce Example • Other Examples

34. Recall Requirements Elicitation Process • The process of requirements elicitation consists of the following steps • Identify Actors • Identify Scenarios • Identify Use Cases • Refine Use Cases • Identify Relationships between actors and Use Cases • Identify Initial Analysis Objects • Identify Non-functional requirements

35. Requirements Elicitation ProcessStep 4. Refining Use Cases System Sequence Diagrams • System sequence diagrams establish the dynamic behavior in terms of key scenarios of the system for each use case • The system sequence diagram models a scenario of the system interactions with the environment for a given use case • Input/output events are clearly identified in each sequence diagram, • The State of the system before and after each event are also depicted • Different diagrams model scenarios with the normal flow of events and the abnormal flow of events

36. Sequence Diagrams and Use CasesSystem Sequence Diagram The use case diagram Of system S The sequence diagram of use case UC1 for system S

37. UML Use Case Diagrams: The Requirements Model Case Study

38. UML Use Case Diagrams: The Requirements Model- System Seq. Diags.Digital Sound Recorder Case Study • A sequence diagram displays object interactions arranged in a time sequence capturing a specific scenario of interactions in a use case supported by the system System Sequence Diagram for Play Massage Scenario: Normal Flow Time

39. Sys. Seq. Diagram for Alarm sounding while playing Massage Scenario

40. Sys. Seq. Diag. for Alarm while stand-by followed by No-power event.

41. The ATM Example

44. This is for the Banking Service Subsystem

47. Example: Use Case Diagram of the E-Commerce System

48. Place Requisition Scenario

49. Confirm Delivery Scenario

50. Send Invoice Scenario