uk.ac.manchester.cs.factplusplusad.BotEquivalenceEvaluator Maven / Gradle / Ivy
package uk.ac.manchester.cs.factplusplusad;
import org.semanticweb.owlapi.model.*;
import org.semanticweb.owlapi.vocab.OWL2Datatype;
/**
* check whether class expressions are equivalent to bottom wrt given locality
* class
*/
class BotEquivalenceEvaluator extends SigAccessor implements OWLObjectVisitor {
/** keep the value here */
boolean isBotEq = false;
/** corresponding top evaluator */
TopEquivalenceEvaluator topEval;
public BotEquivalenceEvaluator(Signature s) {
super(s);
}
/**
* check whether the expression is top-equivalent
*
* @param expr
* expression
* @return true if top equivalent
*/
boolean isTopEquivalent(OWLObject expr) {
return topEval.isTopEquivalent(expr);
}
/**
* non-empty Concept/Data expression
*
* @param c
* class
* @return true iff C^I is non-empty
*/
private boolean isBotDistinct(OWLObject c) {
// TOP is non-empty
if (isTopEquivalent(c)) {
return true;
}
// built-in DT are non-empty
// FIXME!! that's it for now
return c instanceof OWLDatatype;
}
/**
* cardinality of a concept/data expression interpretation
*
* @return true if #C^I > n
* @param c
* class
* @param n
* cardinality
*/
private boolean isCardLargerThan(OWLObject c, int n) {
if (n == 0) {
return isBotDistinct(c);
}
// data top is infinite
if (c instanceof OWLDataRange && isTopEquivalent(c)) {
return true;
}
if (c instanceof OWLDatatype) {
// string/time are infinite DT
OWLDatatype dt = ((OWLDatatype) c).asOWLDatatype();
if (OWL2Datatype.XSD_STRING.matches(dt) || OWL2Datatype.XSD_DATE_TIME.matches(dt)
|| OWL2Datatype.XSD_DATE_TIME_STAMP.matches(dt)) {
return true;
}
}
// FIXME!! try to be more precise
return false;
}
/**
* @param n
* cardinality
* @param r
* property
* @param c
* class
* @return true iff (<= n R.C) is botEq
*/
private boolean isMaxBotEquivalent(int n, OWLPropertyExpression r, OWLPropertyRange c) {
// XXX check
return isBotEquivalent(r) && isCardLargerThan(c, n);
}
/**
* QCRs
*
* @param n
* cardinality
* @param r
* property
* @param c
* class
* @return true iff (>= n R.C) is botEq
*/
private boolean isMinBotEquivalent(int n, OWLPropertyExpression r, OWLPropertyRange c) {
return n > 0 && (isBotEquivalent(r) || isBotEquivalent(c));
}
// set fields
/**
* set the corresponding top evaluator
*
* @param eval
* top evaluator
*/
void setTopEval(TopEquivalenceEvaluator eval) {
topEval = eval;
}
/**
* @param expr
* expression
* @return true iff an EXPRession is equivalent to bottom wrt defined policy
*/
boolean isBotEquivalent(OWLObject expr) {
// XXX check
if (expr.isBottomEntity()) {
return true;
}
if (expr.isTopEntity()) {
return false;
}
expr.accept(this);
return isBotEq;
}
@Override
public void visit(OWLClass expr) {
// XXX check
isBotEq = !topCLocal() && nc(expr);
}
@Override
public void visit(OWLObjectComplementOf expr) {
isBotEq = isTopEquivalent(expr.getOperand());
}
@Override
public void visit(OWLObjectIntersectionOf expr) {
isBotEq = expr.operands().anyMatch(this::isBotEquivalent);
}
@Override
public void visit(OWLObjectUnionOf expr) {
isBotEq = !expr.operands().anyMatch(p -> !isBotEquivalent(p));
}
@Override
public void visit(OWLObjectOneOf expr) {
isBotEq = expr.individuals().count() == 0;
}
@Override
public void visit(OWLObjectHasSelf expr) {
isBotEq = isBotEquivalent(expr.getProperty());
}
@Override
public void visit(OWLObjectHasValue expr) {
isBotEq = isBotEquivalent(expr.getProperty());
}
@Override
public void visit(OWLObjectSomeValuesFrom expr) {
isBotEq = isMinBotEquivalent(1, expr.getProperty(), expr.getFiller());
}
@Override
public void visit(OWLObjectAllValuesFrom expr) {
isBotEq = isTopEquivalent(expr.getProperty()) && isBotEquivalent(expr.getFiller());
}
@Override
public void visit(OWLObjectMinCardinality expr) {
isBotEq = isMinBotEquivalent(expr.getCardinality(), expr.getProperty(), expr.getFiller());
}
@Override
public void visit(OWLObjectMaxCardinality expr) {
isBotEq = isMaxBotEquivalent(expr.getCardinality(), expr.getProperty(), expr.getFiller());
}
@Override
public void visit(OWLObjectExactCardinality expr) {
int n = expr.getCardinality();
isBotEq = isMinBotEquivalent(n, expr.getProperty(), expr.getFiller()) || isMaxBotEquivalent(n, expr
.getProperty(), expr.getFiller());
}
@Override
public void visit(OWLDataHasValue expr) {
isBotEq = isBotEquivalent(expr.getProperty());
}
@Override
public void visit(OWLDataSomeValuesFrom expr) {
isBotEq = isMinBotEquivalent(1, expr.getProperty(), expr.getFiller());
}
@Override
public void visit(OWLDataAllValuesFrom expr) {
isBotEq = isTopEquivalent(expr.getProperty()) && !isTopEquivalent(expr.getFiller());
}
@Override
public void visit(OWLDataMinCardinality expr) {
isBotEq = isMinBotEquivalent(expr.getCardinality(), expr.getProperty(), expr.getFiller());
}
@Override
public void visit(OWLDataMaxCardinality expr) {
isBotEq = isMaxBotEquivalent(expr.getCardinality(), expr.getProperty(), expr.getFiller());
}
@Override
public void visit(OWLDataExactCardinality expr) {
int n = expr.getCardinality();
isBotEq = isMinBotEquivalent(n, expr.getProperty(), expr.getFiller()) || isMaxBotEquivalent(n, expr
.getProperty(), expr.getFiller());
}
@Override
public void visit(OWLObjectProperty expr) {
// XXX check
isBotEq = !topRLocal() && nc(expr);
}
@Override
public void visit(OWLObjectInverseOf expr) {
isBotEq = isBotEquivalent(expr.getInverseProperty());
}
@Override
public void visit(OWLSubPropertyChainOfAxiom expr) {
isBotEq = true;
for (OWLObjectPropertyExpression p : expr.getPropertyChain()) {
if (isBotEquivalent(p)) {
return;
}
}
isBotEq = false;
}
@Override
public void visit(OWLDataProperty expr) {
if (expr.isTopEntity()) {
isBotEq = false;
return;
}
if (expr.isBottomEntity()) {
isBotEq = true;
return;
}
isBotEq = !topRLocal() && nc(expr);
}
@Override
public void visit(OWLDatatype node) {
isBotEq = node.isBottomEntity();
}
@Override
public void visit(OWLLiteral node) {
isBotEq = false;
}
@Override
public void visit(OWLDatatypeRestriction o) {
isBotEq = false;
}
@Override
public void visit(OWLDataComplementOf node) {
isBotEq = isTopEquivalent(node.getDataRange());
}
@Override
public void visit(OWLDataOneOf node) {
isBotEq = node.values().count() == 0;
}
@Override
public void visit(OWLDataIntersectionOf expr) {
if (expr.operands().anyMatch(this::isBotEquivalent)) {
return;
}
isBotEq = false;
}
@Override
public void visit(OWLDataUnionOf expr) {
if (expr.operands().anyMatch(p -> !isBotEquivalent(p))) {
return;
}
isBotEq = true;
}
}