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3.3.1.8 Instances of a class assuming values of known type on any property Pattern
This pattern checks the existence of property values in the knowledge base assumed by
properties of a known type. Then it deducts the instances to which they are being assigned. It
encompasses three exploration components: (i) the Property Component configured with a
PropertyWithType selection condition to retrieve the property with the given type in the
knowledge base, (ii) the Property Value Component configured with a PropertyValueOfProperty
selection condition to retrieve the property values being assumed by the previous properties, and
(iii) the Instance Component configured with a InstanceOfClass and a
InstanceWithPropertyValue selection conditions and the BooleanOperator OR to retrieve the
instances having at least one of the previous property values. The Complex Query class invokes
the query component methods: the type input is transferred to the Property Component, the
deducted properties are transferred to the Property Value Component, the class input and the
deducted property values become the input for the Instance Component, and finally, the deducted
instances are returned to the user.
Figure 3.32: Instances of a class assuming values of known type on any property Pattern
3.3.2 Knowledge Management
The patterns for knowledge management are built on top of the management components for
creating new UML elements or for removing existing ones under certain conditions. The
execution of these patterns has side effects on the knowledge base. Like in the case of
exploration patterns, values are transferred from one component to the other either with user
intervention or automatically. In the latter case, the methods invocation is done by the UML
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