L3-6b-S1 Sequence Diagrams © M.E. Fayad SJSU -- CmpE Software System Engineering Dr. M.E. Fayad, Professor Computer Engineering Department, Room #283I College of Engineering San José State University One Washington Square San José, CA

L3-6b-S2 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad 2 Lesson 3-6b: Sequence Diagrams

L3-6b-S3 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad Lesson Objectives 3 Understand how to generate sequence diagrams Learn the syntax of sequence diagram Explore examples of sequence diagrams

L3-6b-S4 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad Place objects that participate in the interaction at the top of the diagram, across the X-axis –Place the object that initiates the interaction at the left, and increasingly more subordinate objects to the right Place messages the objects send and receive along the Y-axis, in order of increasing time from top to bottom 4 Drawing Sequence Diagrams

L3-6b-S5 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad Use sequence diagrams to model flows of control by time ordering –Do a better job of visualizing simple iteration and branching Use collaboration diagrams to model flows of control by organization –Do a better job of visualizing complex iteration and branching and of visualizing multiple concurrent flows of control 5 Common Uses

L3-6b-S6 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad Sequence diagrams have two features: –Object lifeline Vertical dashed line that represents the existence of an object over a period of time –Focus of control A tall, thin rectangle that shows the period of time during which an object is performing an action, either directly or through a subordinate procedure 6 Sequence Diagrams

L3-6b-S7 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad 7 Syntax of Sequence Diagram

L3-6b-S8 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad 8 Sequence Diagram: Example (1)

L3-6b-S9 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad 9 Sequence Diagram: Example (2)

L3-6b-S10 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad 10 Sequence Diagram: Example (3)

L3-6b-S11 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad 11 Sequence Diagram: Example (4)

L3-6b-S12 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad 12 Sequence Diagram: Example (5)

L3-6b-S13 Sequence Diagrams © M.E. Fayad SJSU – CmpE --- M.E. Fayad T/F: 1.The participants in the sequence diagrams are classes and components 2.The sequences in the sequence diagram are connected. 3.Sequence diagram is an event-trace diagram 4.You can generate a sequence diagram / use case. 5.A sequence diagram models flows of control by time ordering 13 Discussion Questions