Model Parts, Diagrams, Dictionary Items, and Properties > Properties > Data usage (property)
  
Data usage (property)
For automation interface information about the Data Usage property, see Operation (automation interface).
This property specifies whether an Operation's data usage is On Instance, On Class or Both.
On Instance — Specifies that the Operation uses only instance data.
On Class — Specifies that the Operation uses only data from the owning Class, Data Type or Interface. The 'static' keyword is automatically added during code generation.
Both — Specifies that the Operation uses data from both the owning Class, Data Type or Interface, and its instance.
By default:
If a Class owns a new Operation, the On Instance option is selected.
If the Model or Package owns a new Operation, the On Class option is selected.
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If the Model or a Package owns an Operation, Modeler prevents the Data Usage being changed from On Class.
On a Class Diagram, an Operation that has On Class data usage is shown underlined.
This property is set on the Options tab of an Operation's Property Pages.
The following section provides information about the items and diagrams for which Data Usage is a property. For more information about an item or diagram, click it.
Is property of
Operation