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Time Sequence Diagram. Dr. Zhen Jiang West Chester University E-mail: zjiang@wcupa.edu url: www.cs.wcupa.edu/~zjiang. Sequence Diagrams. A sequence diagram is an interaction diagram that focuses on the time ordering of messages
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Time Sequence Diagram Dr. Zhen Jiang West Chester University E-mail: zjiang@wcupa.edu url: www.cs.wcupa.edu/~zjiang
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/library/3101.html
: Pilot : ATC : Radar requestLdgClearance(r) checkWeather checkRunwayClear(r) clear clearance
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.
Samples • Grading system • Shopping system • Ticket/Box system