Class Diagrams

Last updated Nov 8, 2022 Edit Source

+ : public - : private # : protected ~ : package private

Heuristics for identifying entity objects

• Terms that developers or users need to clarify in order to understand the use case • Recurring nouns in the use cases (e.g., Incident)
• Real-world entities that the system needs to track (e.g., FieldOfficer, Dispatcher, Resource)
• Real-world activities that the system needs to track (e.g., EmergencyOperationsPlan)
• Data sources or sinks (e.g., Printer).

Heuristics for identifying boundary objects

• Identify user interface controls that the user needs to initiate the use case (e.g., ReportEmergencyButton).
• Identify forms the users needs to enter data into the system (e.g., EmergencyReportForm).
• Identify notices and messages the system uses to respond to the user (e.g., AcknowledgmentNotice).
• When multiple actors are involved in a use case, identify actor terminals (e.g., DispatcherStation) to refer to the user interface under consideration.

Heuristics for identifying control objects

• Identify one control object per use case.
• Identify one control object per actor in the use case.
• The life span of a control object should cover the extent of the use case or the extent of a user session. If it is difficult to identify the beginning and the end of a control object activation, the corresponding use case probably does not have well-defined entry and exit conditions.