A Second Comprehensive Application Example - Model-Driven and Software Product Line Engineering - page 206

vertical model-to-model transformations since they transform
models between different abstraction levels. The source
abstraction level is the application domain abstraction level,
whereas the target level is the abstraction level including
concerns related to GUI components.
We created base transformation rules to create the
common views in the GUI of a collection manager
system. We created three specific transformation rules to
create GUI:InfoSingleView , GUI:InfoGridView , and
GUI:InfoTreeView . In this case, since these are coarse-
grained variants, which means that the selection of a feature
guides the derivation process without taking into account
model elements, these three transformation rules are created
based only on the feature model without taking into account
either the constraint or the binding models. Thus, for instance,
if the Single feature is selected, one GUI:InfoSingleView
element is created.
Third Stage: Model-to-text transformation rules. The model-
to-text transformation rules produce the source code of product
line members. These transformation rules have as input a
kernel model and a GUI model. The transformation rules are
in charge of creating Java classes at the kernel and GUI layers
to connect them.
7.5.2. Decision models
We explained that we create specific transformation rules
taking into account the possible bindings in binding models,
which satisfy constraints in constraint models. That is, taking
into account fine-grained variations. We need a mechanism for
selecting and executing automatically the base transformation
rules and only some specific transformation rules associated
to fine-grained variations. We proposed the use of explicit
decision models for composition of transformation rules based
on binding models, which implies the modification of a