UML Modeling Techniques > Object interaction modeling > Sequence diagram > Stimuli > Using an event signature to specify name and parameters
  
Using an event signature to specify name and parameters
Through the Signature of an Event, you can perform the following tasks:
Specify the Name of the Event.
Create Parameters for the Event.
Set the Mechanism, Type, Name and Default of each Parameter.
You specify the Name and Parameters of an Event by typing the Signature in the following format:
<event name> ( [<parameters>] )
where:
<event name> is the Event's Name.
<parameters> - is the Event's Parameters. For each parameter
type the following information:
<mechanism> <parameter name> [: <parameter type>] [= <default>]
where:
<mechanism> is the Parameter's Mechanism. Type either 'in', 'out', or 'in out'. If you do not type a mechanism, Modeler sets the Mechanism to 'in'.
<parameter name> is the Parameter's Name.
<parameter type> is the Parameter's Type. Modeler attempts to match the text you type with items that can be used as Types in the model. If a match is found, the item is referenced as the Type. If no match is found, an uninterpreted type is created. If you do not type any text for <parameter type>, the Type is left blank. Ensure that you prefix the parameter type with a colon.
<default> is the Parameter's Default. If you do not type any text for <default>the Default is left blank.
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If the Parameter's signature is greater than 200,000 characters, the Default value is not included in the signature. If the Default value is not included and you change the signature, the Default value will not be changed. If the Default value is not included and you want to clear the Default value through the signature, you must include '= ' at the end of the signature. Ensure that you prefix a default value with an equals character.
You can change the Event's Signature through the Event's Property Pages.
After creating an Event, type the following text in the Signature property: Set Alarm (in Status : short = off)
The preceding Event Signature performs the following tasks:
Changes the Name of the Event to Set Alarm.
Creates a Parameter named Status:
Sets the Mechanism of the Parameter to 'in'.
Sets the Type of the Parameter to short, referencing the short Basic Type.
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When a Parameter appears on the Items tab of an Event's Property Pages
you can specify the Parameter's Mechanism, Name, Type and Default through the <mechanism> <parameter name> [: <parameter type>] [= <default>] syntax.