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UML Use Case
Graphical notation
A Use Case symbol, denoted graphically by an ellipse, represents a particular scenario in a system. By default, the name of the Use Case is centered within of the symbol.
This graphic is described in the surrounding text.
You can change this default for a particular Use Case by selecting the Use Case symbol, and selecting Format, Symbol Format, Text Position. This brings up the Text Position dialog, which enables you to set the position of the Use Case name in relation to its symbol. For example, you can toggle on the Position Outside, Name selection so that the name is drawn outside the Use Case symbol.
You can change the default for new Use Cases by selecting a Use Case symbol already drawn and choosing Format, Symbol Format, Symbol Style, Text.
Standard definition
A Use Case is typically defined with text which describes the scenario. You can enter the text in the Description field within the Use Case definition. You can also choose to describe the scenario in terms of its steps, using the Use Case Steps field within the Use Case definition. Other properties are provided as a default for defining a Use Case, such as pre- and post-conditions.
Reference documents
You can specify an external document, spreadsheet, url, or other file in the Reference Documents property of a Use Case.
1 Click Browse Externally to select a document in any directory on your computer or network.
2 Click Browse Internally to browse and select a file in the Files table of the encyclopedia’s database.
If you open an internal document, it will actually be exported from the Files table and opened (in the default program set on your computer for that type of document). You receive a warning message that you must remember to import it back into the Files table of the database after saving it.
3 Select the document or file in the Reference Documents list, and click the Open button to open the document in the program that you have set as default on your computer.
Customized definition to reflect the business being modeled
The System Architect customizable repository provides more power for the Use Case than perhaps any other graphical element of UML. A Use Case definition should model all relevant properties of scenarios within a business. Many of these properties are unique to the business or industry that is being modeled. You can add new properties to a Use Case definition through USRPROPS.TXT.
See also
UML Use Case diagram