A use case definition specifies the required behavior of its subject relative to one or more external actors. The objective of the use case is to provide an observable result of value to one or more of its actors. The subject and the actors interact in order to achieve this objective. A use case usage is a usage of a use case definition.

Creating use case usage and definition elements

Creating use case usage and definition elements via the Textual Editor

To create use case usage and definition elements via the Textual Editor

  1. In the Textual Editor, place the cursor where you want to create the element and declare the keyword:

    1.  use case def for a use case definition.

    2.  use case for a use case usage.
  2. Specify the element name.
  3. (Optional) Specify the use case's features in the element body. 
  4. Click the Synchronize button.

use case def 'Provide Transportation' {                    // use case definition
    subject vehicle : Vehicle;
    actor driver : Person;
    actor environment : Environment;
}

use case 'drive vehicle' : 'Provide Transportation';   // use case usage

Creating use case usage and definition elements via the Create Element command

To create use case usage and definition elements via the Create Element command

  1. In the Containment tree, right-click an element, and in the shortcut menu, click Create Element.

  2. In the Create Element submenu, select one of the following:
    1. use case def to create a use case definition element.
    2. use case to create a use case usage element.
  3. Name the element.
  4. (Optional) Specify the use case's features.

Creating use case usage and definition elements via the view palette

To create use case usage and definition elements via the view palette

  1. In the view palette, under the Cases group, click one of the following:
    1. The use case def button to create a use case definition element.
    2. The use case button to create a use case usage element.

      If the needed button is not displayed, click the down-facing arrow next to either the use case or the use case def button and select the needed button in the dropdown menu.

  2. Click in the view pane where you want to create the use case symbol.
  3. (Optional) Specify the use case's features.

Auto-creating use case definition elements via the Extract Definition command

To auto-create use case definition elements via the Extract Definition command 

Auto-creating use case usage elements via the Extract Usage command

To auto-create use case usage elements via the Extract Usage command