SEKE 2012 Proceedings - Knowledge Systems Institute

ize:Class”, with an empty precondition set, and with the only
effect being the proposition “specialization(Class)”, where
Class is the name of the class that contains the method being
overwritten.
Let us use the Diagram from figure 2 as an example. This
diagram represents the sequence for updating a screen in the
SWING framework. To use this function, it is necessary to
overwrite the method paint of a class that specializes a “Panel”.
Then this mechanism must be started by the method “validate”
from a “JFrame” object. Once overwritten, it is possible to use
an object of the type “Graphics”. Using this information, the
following operators are made:
Name : overwrite:Panel.paint
PC : sequence(Update Screen),
link(JFrame, Panel), specialization(Panel)
E : object(Graphics)
Name : specialize:Panel
PC : {}
E : specialization(Panel)
IV. CREATING SEQUENCE DIAGRAMS
To make the sequence diagrams, a partial order planner
is used. The planner requires three inputs: a set of possible
operators, a goal state and an initial state. The possible
operators are the ones constructed based on the framework
model. The goal state will be a state composed of a proposition
“interface(Target Interface)”, representing the interface that the
user wishes to execute and an empty initial state will be used,
so that it is considered that no element of the framework is
currently being used.
Fig. 5: Sequence diagram resulting from the plan from figure 4
Activities Diagram shown in figure 6. This diagram shows the
application needs to first create a window, then ask the user to
choose an image file, then print the selected file in the screen.
Fig. 4: Plan for the goal “interface(Create Window)”
Using these inputs, the planner will generate a sequence
of operators that will allow the correct use of the desired
interface. Using this plan, a sequence diagram is made in such
a way that the methods it contains reflect the order of the
operators used in the plan.
For example, let us consider a user that wishes to use
the interface “Create Window” from the SWING framework.
First, all the operators from the framework would be extracted,
following the steps described in section III. Next, the planner
would be initialized with an empty state, the framework operators
and the goal “interface(Create Window)”. This would
result in the plan shown in figure 4. Next, based on this plan,
the sequence diagram shown in figure 5 can be constructed.
This is a very simple example of how this method can
be used. It becomes more interesting when a sequence of
interfaces is desired, using it as the description for the behavior
of an application.
Suppose, then, a simple application for visualizing images.
One possible way to model this application behavior is by the
Fig. 6: Activity Diagram of the Image Viewer Application
To complete this application model, let us use a simple Class
Diagram, composed of only one class with a single method,
responsible for the sequence of actions. Such diagram is shown
in figure 7.
Fig. 7: Class Diagram of the Image Viewer Application
Using the activities described in figure 6 as the goals
for the application, we get the sequence of propositions:
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