1. Time Sequence Diagram Dr. Zhen Jiang West Chester University E-mail: zjiang@wcupa.edu url: www.cs.wcupa.edu/~zjiang

2. Sequence Diagrams A sequence diagram is an interaction diagram that focuses on the time ordering of messages A vertical dashed line is used to represent the lifetime of an object (it’s the object’s lifeline) A focus of control is a tall, thin rectangle that shows the period of time during which an object is performing an action Details can be found at http://www.ibm.com/developerworks/rational/libra ry/3101.html http://www.ibm.com/developerworks/rational/libra ry/3101.html

3. : ATC checkWeather : Radar requestLdgClearance(r) checkRunwayClear(r) clear clearance : Pilot

5. Tips for Time Sequence Diagram The lifetime of an object is expressed by a rectangle box. It must show when the object starts and when it ends. For different objects with the same class, separated boxes are needed. The time sequence (which action is conducted first) depends on the execution of objects, NOT user. “…” will be used in only two places. No lifetime box for user. All interface classes must be in interface level. Any display results using interface objects must be seen in time sequence diagram. Interface must be organized.

6. Samples Grading system Shopping system Ticket/Box system