7.2.2 XMI Transformations and Triggers

Below is the representation of an operation as expressed in an XMI 1.0 file. The places that contain information we are interested in are set in boldface:

<Foundation.Core.Operation xmi.id="xmi.1632">  
                          <!-- 1. operation id  -->
  <Foundation.Core.ModelElement.name>printStackTrace
                                     <!-- 2. operation name  -->
  </Foundation.Core.ModelElement.name>
  <Foundation.Core.ModelElement.visibility xmi.value="public"/>
                                     <!-- 3. operation visibility  -->
  <Foundation.Core.ModelElement.isSpecification xmi.value="false"/>
  <Foundation.Core.Feature.ownerScope xmi.value="instance"/>
  <Foundation.Core.BehavioralFeature.isQuery xmi.value="false"/>
  <Foundation.Core.Operation.isAbstract xmi.value="false"/>
  <Foundation.Core.Feature.owner>
    <Foundation.Core.Classifier xmi.idref="xmi.1605"/>
                            <!-- 4. operation context  -->
  </Foundation.Core.Feature.owner>
  ...
</Foundation.Core.Operation>

<xmitransformation modelelement="operation"
                   xmipattern="Foundation.Core.Operation" recurse="true">
  <trigger name="id" type="attrval" attr="xmi.id" />
  <trigger name="name" type="ctext" src="Foundation.Core.ModelElement.name" />
  <trigger name="visibility" type="cattrval"
           src="Foundation.Core.ModelElement.visibility" attr="xmi.value"/>
  <trigger name="context" type="gcattrval"
           src="Foundation.Core.Feature.owner" attr="xmi.idref"/>
</xmitransformation>

• attribute modelelement (required): the SDMetrics metamodel element for which this transformation is defined. In our case, it's the operation.
• attribute xmipattern (required): the XMI element that represents our UML element. In XMI 1.0, operations are specified with the XMI element "Foundation.Core.Operation"
• attribute recurse (optional): is set to true if the model element can serve as context for subelements. In our case, operations can have parameters as subelements, so we set the attribute to true (the XMI transformation for parameters is taken care of in a separate XMI transformation).
• attributes requirexmiid and allowxmiidref (optional): used to extract information from XMI elements that have no XMI ID of their own. We'll discuss these attributes in Section 7.2.3.5 "Optional XMI ID".
• attribute condition (optional): specify a condition for the attributes of the XMI element that must be fulfilled for this XMI transformation to become effective. Conditional XMI transformations will be discussed in Section 7.2.3.6 "Conditional XMI Transformations".

• attribute type: indicates how the trigger retrieves information from the XMI file. The type can be one of the following: attrval, ctext, cattrval, gcattrval, constant, ignore, and xmi2assoc.
• attribute name: the name of the SDMetrics metamodel attribute to which this trigger pertains. In the above example, each trigger refers to exactly one attribute of the operation metamodel element: id, name, visibility, context.