Derived features
Derived features were added in version 2.0 of the model weaver.
By definition derived features are features that are calculated over
other features. We can not save a derived feature, only the features
that are used in the calculation.
In the model weaver V2.0 the metamodel was changed to enable
deriving references, e.g., the user may define a derived reference that
is a set of others references. It was defined in the KM3 syntax and it
is supported by the weaver workbench. The user may define for example
supplier/consumer that are a subset of an order reference.
In the user interface, derived features are indicated by "<" and
">" in the menus, for example "<orders>
supplier" and "<orders>
consumer". In this case, only supplier
and consumer are
saved in the .ecore file.
Model weaver ID generation mechanism
The user may choose between specific ID generation mechanisms for each
object. The ID mechanism is used to reference each woven object.
This mechanism is implemented by an association with WModelRef elements. The user can
choose a WModelRef in the
second wizard page, one for each woven model(see interface). It means every
woven object from the same model has the same identification mechanism.
In the standard extension we have defined two mechanisms to create IDs:
URI XPointer based (the default EMF way to identify an object). For
this the user choose ModefRef. The
other mechanism creates a XMI ID for every created object. It is linked
with ModelRefXMI.