Package org.aksw.deer.enrichments

Class DereferencingEnrichmentOperator

  • All Implemented Interfaces:
    DeerExecutionNode, DeerPlugin, EnrichmentOperator, ParameterizedEnrichmentOperator, Learnable, ReverseLearnable, SelfConfigurable, ParameterizedDeerExecutionNode, ExecutionNode<Model>, Parameterized, Plugin, org.pf4j.ExtensionPoint
    @Extension
public class DereferencingEnrichmentOperator
extends AbstractParameterizedEnrichmentOperator
implements ReverseLearnable, SelfConfigurable
    An EnrichmentOperator for dereferencing.

    Dereferencing is a method of expanding knowledge of resources that belong to an external knowledge base. We define a dereferencing operation as the following sequence of operations:

    1. Query the local model for starting resources ?x that belong to an external knowledge base
    2. Query the external knowledge base for triples (?x, d, ?y), where d is a defined property path in the external knowledge base.
    3. Add all results to the local model in the form of (?x, i, ?y), where i is the property name under which they should be imported.

    Configuration

    :operations

    Each operation corresponds to one dereferencing operation, allowing multiple dereferencing operations being carried out by a single DereferencingEnrichmentOperator. Each entry may contain the following properties:
    :lookUpProperty range: resource
    Determines the starting resources ?x as all objects of triples having the value of :lookUpProperty as predicate.
    :lookUpPrefix [required] range: string
    Determines the starting resources ?x as all objects of triples having the value of :lookUpProperty as predicate.
    :dereferencingProperty [required] range: resource
    Look up the values to be imported to the local model in the external knowledge base using the property defined by the value of :dereferencingProperty.
    :importProperty [required] range: resource
    Add looked up values to starting resources using the value of :importProperty.

    Example