/// <summary>
/// Adds the "aFact -> objectProperty -> bFact" relation to the data
/// </summary>
public RDFOntologyData AddAssertionRelation(RDFOntologyFact aFact,
RDFOntologyObjectProperty objectProperty,
RDFOntologyFact bFact)
{
if (aFact != null && objectProperty != null && bFact != null)
{
//Enforce preliminary check on usage of BASE properties
if (!RDFOntologyChecker.CheckReservedProperty(objectProperty))
{
//Enforce taxonomy checks before adding the assertion
//Creation of transitive cycles is not allowed (OWL-DL)
if (RDFOntologyChecker.CheckTransitiveAssertionCompatibility(this, aFact, objectProperty, bFact))
{
this.Relations.Assertions.AddEntry(new RDFOntologyTaxonomyEntry(aFact, objectProperty, bFact));
}
else
{
//Raise warning event to inform the user: Assertion relation cannot be added to the data because it violates the taxonomy transitive consistency
RDFSemanticsEvents.RaiseSemanticsWarning(String.Format("Assertion relation between fact '{0}' and fact '{1}' with transitive property '{2}' cannot be added to the data because it would violate the taxonomy consistency (transitive cycle detected).", aFact, bFact, objectProperty));
}
}
else
{
//Raise warning event to inform the user: Assertion relation cannot be added to the data because usage of BASE reserved properties compromises the taxonomy consistency
RDFSemanticsEvents.RaiseSemanticsWarning(String.Format("Assertion relation between fact '{0}' and fact '{1}' cannot be added to the data because usage of BASE reserved properties compromises the taxonomy consistency.", aFact, bFact));
}
}
return(this);
}
/// <summary>
/// Checks if the given "aFact -> objectProperty -> bFact" has transitive assertions
/// which would cause transitive cycles (unallowed concept in OWL-DL)
/// </summary>
internal static Boolean CheckTransitiveAssertionCompatibility(RDFOntologyData ontologyData,
RDFOntologyFact aFact,
RDFOntologyObjectProperty objectProperty,
RDFOntologyFact bFact)
{
return(!ontologyData.CheckIsTransitiveAssertionOf(bFact, objectProperty, aFact));
}
/// <summary>
/// Checks if the given childproperty can be set subpropertyof the given motherproperty
/// </summary>
internal static Boolean CheckSubPropertyOfCompatibility(RDFOntologyPropertyModel propertyModel,
RDFOntologyObjectProperty childProperty,
RDFOntologyObjectProperty motherProperty)
{
return(!propertyModel.CheckIsSubPropertyOf(motherProperty, childProperty) &&
!propertyModel.CheckIsEquivalentPropertyOf(motherProperty, childProperty));
}
/// <summary>
/// Checks if the given aproperty can be set equivalentpropertyof the given bproperty
/// </summary>
internal static Boolean CheckEquivalentPropertyCompatibility(RDFOntologyPropertyModel propertyModel,
RDFOntologyObjectProperty aProperty,
RDFOntologyObjectProperty bProperty)
{
return(!propertyModel.CheckIsSubPropertyOf(aProperty, bProperty) &&
!propertyModel.CheckIsSuperPropertyOf(aProperty, bProperty));
}
/// <summary>
/// Removes the "aFact -> objectProperty -> bFact" relation from the data
/// </summary>
public RDFOntologyData RemoveAssertionRelation(RDFOntologyFact aFact,
RDFOntologyObjectProperty objectProperty,
RDFOntologyFact bFact)
{
if (aFact != null && objectProperty != null && bFact != null)
{
this.Relations.Assertions.RemoveEntry(new RDFOntologyTaxonomyEntry(aFact, objectProperty, bFact));
}
return(this);
}