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package rsacomb
import org.semanticweb.owlapi.model.{
OWLOntology,
OWLClass,
OWLSubObjectPropertyOfAxiom,
OWLSubClassOfAxiom,
OWLObjectProperty,
OWLObjectPropertyExpression,
OWLObjectSomeValuesFrom
}
import tech.oxfordsemantic.jrdfox.logic.{
IRI,
BodyFormula,
Atom,
Rule,
Term,
Variable
}
import scala.collection.JavaConverters._
object ProgramGenerator {
def apply(
ontology: OWLOntology,
term: Term,
unsafe: List[OWLObjectPropertyExpression] = List()
): RDFoxAxiomConverter =
new ProgramGenerator(ontology, term, unsafe)
def generateRoleRules(
roles: List[OWLObjectPropertyExpression]
): List[Rule] = {
def additional(pred: String): Seq[Rule] = {
val varX = Variable.create("X")
val varY = Variable.create("Y")
Seq(
Rule.create(
Atom.rdf(varX, IRI.create(pred), varY),
Atom.rdf(varX, IRI.create(pred ++ RSASuffix.Forward.getSuffix), varY)
),
Rule.create(
Atom.rdf(varX, IRI.create(pred), varY),
Atom.rdf(varX, IRI.create(pred ++ RSASuffix.Backward.getSuffix), varY)
),
Rule.create(
Atom.rdf(
varY,
IRI.create(pred ++ RSASuffix.Backward.getSuffix ++ "_inv"),
varX
),
Atom.rdf(varX, IRI.create(pred ++ RSASuffix.Forward.getSuffix), varY)
),
Rule.create(
Atom.rdf(
varY,
IRI.create(pred ++ RSASuffix.Forward.getSuffix ++ "_inv"),
varX
),
Atom.rdf(varX, IRI.create(pred ++ RSASuffix.Backward.getSuffix), varY)
)
)
}
roles
.filter(_.isInstanceOf[OWLObjectProperty]) // Can we avoid this?
.map(_.asInstanceOf[OWLObjectProperty].getIRI.getIRIString)
.flatMap(additional)
}
}
class ProgramGenerator(
ontology: OWLOntology,
term: Term,
unsafe: List[OWLObjectPropertyExpression]
) extends RDFoxAxiomConverter(term, unsafe, SkolemStrategy.None, RSASuffix.None)
with RSAOntology
with RSAAxiom {
import RDFoxUtil._
def rules1(axiom: OWLSubClassOfAxiom): (List[Rule], List[Atom]) = {
val unfold = ontology.cycle(axiom).toList
// Fresh Variables
val v0 = IRI.create("v0_" ++ axiom.hashCode.toString)
val varX = Variable.create("x")
// Predicates
val atomA: Atom = {
val cls = axiom.getSubClass.asInstanceOf[OWLClass].getIRI
Atom.rdf(varX, IRI.RDF_TYPE, cls)
}
def notIn(t: Term): Atom = {
Atom.rdf(
t,
RSA.internal("notIn"),
RSA.internal(unfold.hashCode.toString)
)
}
val roleRf: Atom = {
val visitor =
new RDFoxPropertyExprConverter(varX, v0, RSASuffix.Forward)
axiom.getSuperClass
.asInstanceOf[OWLObjectSomeValuesFrom]
.getProperty
.accept(visitor)
.head
}
val atomB: Atom = {
val cls = axiom.getSuperClass
.asInstanceOf[OWLObjectSomeValuesFrom]
.getFiller
.asInstanceOf[OWLClass]
.getIRI
Atom.rdf(v0, IRI.RDF_TYPE, cls)
}
(
List(
Rule.create(roleRf, atomA, notIn(varX)),
Rule.create(atomB, atomA, notIn(varX))
),
unfold map notIn
)
}
def rules2(axiom: OWLSubClassOfAxiom): List[Rule] = {
val roleR =
axiom.getSuperClass
.asInstanceOf[OWLObjectSomeValuesFrom]
.getProperty
if (ontology.confl(roleR) contains roleR) {
// Fresh Variables
val v0 = IRI.create("v0_" ++ axiom.hashCode.toString)
val v1 = IRI.create("v1_" ++ axiom.hashCode.toString)
val v2 = IRI.create("v2_" ++ axiom.hashCode.toString)
// Predicates
def atomA(t: Term): Atom = {
val cls = axiom.getSubClass.asInstanceOf[OWLClass].getIRI
Atom.rdf(t, IRI.RDF_TYPE, cls)
}
def roleRf(t1: Term, t2: Term): Atom = {
val visitor = new RDFoxPropertyExprConverter(t1, t2, RSASuffix.Forward)
roleR.accept(visitor).head
}
def atomB(t: Term): Atom = {
val cls = axiom.getSuperClass
.asInstanceOf[OWLObjectSomeValuesFrom]
.getFiller
.asInstanceOf[OWLClass]
.getIRI
Atom.rdf(t, IRI.RDF_TYPE, cls)
}
//Rules
List(
Rule.create(roleRf(v0, v1), atomA(v0)),
Rule.create(atomB(v1), atomA(v0)),
Rule.create(roleRf(v1, v2), atomA(v1)),
Rule.create(atomB(v2), atomA(v1))
)
} else {
List()
}
}
def rules3(axiom: OWLSubClassOfAxiom): List[Rule] = {
val cycle = ontology.cycle(axiom).toList
val roleR =
axiom.getSuperClass
.asInstanceOf[OWLObjectSomeValuesFrom]
.getProperty
// Fresh Variables
val v1 = IRI.create("v1_" ++ axiom.hashCode.toString)
// Predicates
def atomA(t: Term): Atom = {
val cls = axiom.getSubClass.asInstanceOf[OWLClass].getIRI
Atom.rdf(t, IRI.RDF_TYPE, cls)
}
def roleRf(t: Term): Atom = {
val visitor =
new RDFoxPropertyExprConverter(t, v1, RSASuffix.Forward)
roleR.accept(visitor).head
}
val atomB: Atom = {
val cls = axiom.getSuperClass
.asInstanceOf[OWLObjectSomeValuesFrom]
.getFiller
.asInstanceOf[OWLClass]
.getIRI
Atom.rdf(v1, IRI.RDF_TYPE, cls)
}
cycle.flatMap { x =>
List(
Rule.create(roleRf(x), atomA(x)),
Rule.create(atomB, atomA(x))
)
}
}
override def visit(axiom: OWLSubClassOfAxiom): List[Rule] = {
if (axiom.isT5) {
// TODO: get role in T5 axiom
// Assuming one role here
val role = axiom.objectPropertyExpressionsInSignature(0)
if (unsafe.contains(role)) {
val visitor =
new RDFoxAxiomConverter(
term,
unsafe,
SkolemStrategy.Standard(axiom.toString),
RSASuffix.Forward
)
axiom.accept(visitor)
} else {
val (r1, f1) = rules1(axiom)
val r2 = rules2(axiom)
val r3 = rules3(axiom)
r1 ++ r2 ++ r3
}
} else {
// Fallback to standard OWL to LP translation
super.visit(axiom)
}
}
override def visit(axiom: OWLSubObjectPropertyOfAxiom): List[Rule] = {
// TODO: Generate additional rules for role inclusion
val additional = List()
super.visit(axiom) ++ additional
}
}
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