Tools Support - Model-Driven and Software Product Line Engineering - page 171

defines the constraint's cardinality property, and a description
associated with the constraint.
Figure 6.8. Eclipse view of the constraint models creator
When a product line architect chooses to save a constraint
model, the plug-in performs two activities. First, it saves
a file with extension .constraint metamodel containing the
constraint model. Second, it saves a file with extension .chk
that contains the Check expressions to validate binding
models against the constraint model. Listing 6.2 presents an
example of a Check expression generated by the Constraint
Models Creator. The expression is generated from a constraint
specifying that at least one Door element bound to the feature
Lock Door Control has to exist in the binding model being
validated.
Our current implementation of the Constraint Models
Creator allows product line architects to create the constraint
properties associated with constraints. This implementation