8.1.1.6 Filter Attribute "scope"

With the "scope" attribute, you can filter for elements that fulfill a condition for the scope:

<metric name="SameScope_SupplierClasses" domain="class"> 
  <description>The number of supplier classes of a client 
  class defined in the same scope.</description>
  <projection relation="depclient" target="dependency"
    element="depsupplier" eltype="class" scope="same"/>
</metric>

• same: the projected element is in the exact same scope. In Figure 35 below, Class1 and Class2 are in the same scope. So are Class3 and Class4.
• other: the projected element is not in the same scope. In Figure 35 below, this applies to all class pairs except Class1&Class2 and Class3&Class4.
• higher: the projected element is higher in the scope hierarchy. E.g., for Class3, only Class1 and Class2 are higher in the scope hierarchy. The same holds for Class4 and Class6. For Class 5, all classes except Class6 are higher in the hierarchy. Class6 is on a different branch, hence not higher or lower than Class5.
• lower: the projected element is lower in the scope hierarchy. For Class3, only Class5 is lower in the hierarchy. For Class1, all classes except Class2 are lower.
• nothigher: the inverse of "higher". For Class3, the following classes are not higher in the scope hierarchy: Class4 (because it's in the same scope), Class5 (because it's lower) and Class6 (because it's on a different branch).
• notlower: the inverse of "lower". For Class3, all classes but Class5 are not lower in the scope hierarchy.
• sameorhigher: the projected element is in the same scope or higher scope. E.g., for class4, that would be Class1, Class2, and Class3.
• sameorlower: the projected element is in the same scope or lower scope. Again, for Class4, that would be Class3 and Class5.
• samebranch: same or higher or lower scope. For Class1 and Class2, this includes all classes. For Class3, Class4, and Class5, this includes all classes but Class6.
• notsamebranch: the inverse of "samebranch". For Class6, this would be classes Class3, Class4, and Class5. All other class pairs are on the same branch.

In the above cases, we compared the scope of two elements. There are four more values we can specify for scope: idem/notidem, and containedin/notcontainedin. These test if the element for which the metric is calculated is/is not the scope of the projected element.

For example, we want to define a package coupling metric that counts the number of stimuli sent to instances of classes in the package, from instances of classes outside the package (i.e., stimuli that cross the package boundary).

We assume we have already defined for packages the set "StimRecvSet" of stimuli received by object instances of classes in the package. We need to check, for each stimulus in that set, if type of the sender is a class that is not defined in the current package:

<metric name="StimRecv_ex" domain="package">
   <description>The number of stimuli received by object instances 
                 of classes outside the package.</description>
   <projection relset="StimRecvSet" target="stimulus"
     element="stimsender.objtype.context" scope="notidem" />
</metric>

To further illustrate the new scope comparisons, consider again the example package hierarchy in Figure 35. The additional values for attribute scope are:

• idem: only return elements identical to the element for which the metric/set is calculated. Using "idem" as scope in metric "StimRecv_ex" above would count the stimuli sent between instances of classes of the package. For package1.1 in Figure 35, this would be stimuli sent within or between instances of Class3 and Class4.
• notidem: only return elements not identical to the element for which the metric/set is calculated. For package1.1, these are stimuli sent from Class1, Class2, Class5, and Class6.
• containedin: only returns elements that are identical to or contained in the element for which the metric/set is calculated. Using "containedin" as scope in metric "StimRecv_ex" above would count stimuli sent to instances of classes of the package from instances of classes of the package, or any of its subpackages. For package1.1, these are Class3, Class4, and Class5.
• notcontainedin: only return elements that are not contained in the element for which the metric/set is calculated. Using "notcontainedin" as scope in metric "StimRecv_ex" above would count stimuli sent to instances of classes of the package from instances of classes outside the package and any of its subpackages. For package1.1, these are stimuli sent from Class1, Class2, and Class6.