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SWE 205 - Introduction to Software Engineering
Lecture 16 – System Modeling
An Example
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Lecture Objectives Object-Oriented Analysis - An example
Safe-Home System
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Object-Oriented Analysis Basic user requirements must be
communicated between the customer and the software engineer.
Classes must be identified. A class hierarchy is defined. Object-to-object relationship should be
represented. Re-apply the above tasks iteratively until the
model is complete.
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Safe-Home surveillance system - Home Owner Access camera surveillance via the
internet. Select camera to view. Request thumbnails from all cameras. Control panel and zoom for a specific
camera. Selectively record camera output.
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Use Case: Access camera surveillance Actor - Homeowner Please refer to the handout for the
detailed use case description.
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Use Case: Access camera surveillance The homeowner select ‘pick a camera’. The system displays the floor plan of
the house.
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Use Case: Access camera surveillance Can the actor take some other action at
this point? Is it possible that the actor will
encounter some error condition at this point?
Is it possible that the actor will encounter some other behavior at this point?
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Activity Diagram UML activity diagram supplements the
use case by providing a graphical representation of the flow of interaction within a specific scenario.
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Swim-lane Diagrams UML swim-lane diagram is a useful
variation of the activity diagram Allows the modeler to represent the flow
of activities described by use case; and Indicate which actor or analysis class
has responsibility for the action described by an activity rectangle.
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Key points Use Case Diagrams Activity Diagrams
Swim-lane Diagrams