1. UML Diagrams: Sequence Diagrams The Requirements Model, and The 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. UML Development - Overview
ACTORS
USE CASES
REQUIREMENTS
ELICITATION
Time
SCENARIOS D
Requirements
Engineering
System/Object
SEQUENCE
DIAG. A T A
ANALYSIS
CLASS DIAGRAM(S)
ANALYSIS
Specify Domain
Objects
StateChart
DIAGRAMs 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
Detailed DESIGN R 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
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 Diagrams Showing 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 Process Step 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 Cases System 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
Study

38. UML Use Case Diagrams: The Requirements Model- System Seq. Diags
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

51. Confirm Shipment Scenario

53. Another Example: Pace Maker Use-Case model

54. Pace Maker Sys. Seq. Diag

55. Seq. Diag. at the object level (The Analysis Model)

56. A Simple Example of Using UML2
EXAMPLE: SATELLITE CONTROL SYSTEM

57. Example of Software Architecture Using UML2
SATELLITE CONTROL SYSTEM Architecture

58. A Simple Example Using UML2
SATELLITE CONTROL SYSTEM Architectural behavior