@Override
public NormalFormGCI getNormalForm() {
final NormalFormGCI result;
// try {
if (lhs instanceof Concept) {
if (rhs instanceof Concept) {
final int newLhs = lhs.hashCode();
result = NF1a.getInstance(newLhs, rhs.hashCode());
} else if (rhs instanceof Existential) {
final Existential existential = (Existential) rhs;
result =
NF2.getInstance(
lhs.hashCode(), existential.getRole(), existential.getConcept().hashCode());
} else if (rhs instanceof Datatype) {
final Datatype datatype = (Datatype) rhs;
result = NF7.getInstance(lhs.hashCode(), datatype);
} else {
throw new IllegalStateException(
"GCI is not in Normal Form: "
+ "lhs is Concept but rhs is neither Concept, "
+ "Existential nor Datatype; it is "
+ rhs);
}
} else if (lhs instanceof Conjunction) {
final Conjunction conjunction = (Conjunction) lhs;
final AbstractConcept[] concepts = conjunction.getConcepts();
if (concepts.length == 1) {
result = NF1a.getInstance(concepts[0].hashCode(), rhs.hashCode());
} else if (concepts.length == 2) {
result = NF1b.getInstance(concepts[0].hashCode(), concepts[1].hashCode(), rhs.hashCode());
} else {
throw new IllegalStateException(
"Conjunction should have exactly one or two "
+ "Concepts not "
+ concepts.length
+ ": "
+ conjunction);
}
} else if (lhs instanceof Existential) {
Existential existential = (Existential) lhs;
result =
NF3.getInstance(
existential.getRole(), existential.getConcept().hashCode(), rhs.hashCode());
} else if (lhs instanceof Datatype) {
Datatype datatype = (Datatype) lhs;
result = NF8.getInstance(datatype, rhs.hashCode());
} else {
throw new IllegalStateException("GCI is not in Normal Form: " + lhs + ", " + rhs);
}
return result;
}
/**
* B ⊑ ∃r.C' → {B ⊑ ∃r.A, A ⊑ C'}
*
* @param gcis
* @return
*/
boolean rule6(final IFactory factory, final Inclusion[] gcis) {
boolean result = false;
if (rhs instanceof Existential) {
Existential existential = (Existential) rhs;
final AbstractConcept cHat = existential.getConcept();
if (!(cHat instanceof Concept)) {
result = true;
Concept a = getA(factory, cHat);
gcis[0] = new GCI(lhs, new Existential(existential.getRole(), a));
gcis[1] = new GCI(a, cHat);
}
}
return result;
}