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actors to roles. Therefore, structural entities identified by intertype declarations
can certainly be described with UCM components. The resulting map is called
advice map
. An advice map does not differ syntactically from a non-aspectual
map. Both describe behavior with a path, and both use components to indicate
who is responsible for providing the behavior. The difference manifests itself in
terms of how this map fits into the overall system. This is explained in Sect. 3.4.
A
B
e1
s1
r1
r3
C
r2
Fig. 8.
Advicemapwithpathandcomponents
Figure 8 shows the description of an advice that requires
r1
from component
A
, responsibility
r2
from component
C
, and responsibility
r3
from component
B
.
All three components are contributing to the advice. There are three cases:
a. An advice may use an already existing responsibility.
b. An advice may add an aspect-specific responsibility to an already existing
component.
c. An advice may define an aspect-specific responsibility for an aspect-specific
component.
These three cases can of course be automatically identified by looking at the
usage of the responsibilities and components in the whole UCM model, but there
is no standard visual representation that indicates which case applies. Therefore,
the differentiation between these three casesisamatterofnamingconventions.
For example,
A
could be called
A(Shared)
to indicate case (a),
B
could be called
B (Extended)
to indicate case (b), and
C
could be called
C (Owned)
to indicate
case (c).
3.3
Pointcut Map
A pointcut defines a set of joinpoints either explicitly or in a parameterized way,
thereby defining the structural context and behavioral context for the execution
of an advice. In aspect-oriented programming, pointcuts can be rather lengthy
and complex multi-line expressions. In aspect-oriented use case modeling, point-
cuts reference extension points in a different use case. Both use text as the means
to describe pointcuts. Considering the visual character of UCMs, a visual rep-
resentation for pointcuts is a natural choice. More importantly, using a visual
representation instead of defining separate textual representations of pointcuts
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