it.unibz.inf.ontop.constraints.ImmutableCQContainmentCheck Maven / Gradle / Ivy
package it.unibz.inf.ontop.constraints;
import com.google.common.collect.ImmutableCollection;
import com.google.common.collect.ImmutableSet;
import it.unibz.inf.ontop.model.atom.AtomPredicate;
import it.unibz.inf.ontop.model.atom.DataAtom;
import java.util.Iterator;
import java.util.List;
import java.util.ListIterator;
public interface ImmutableCQContainmentCheck {
/**
* Returns true if the query cq1 is contained in the query cq2
* (in other words, the first query is more specific, it has fewer answers)
*
* @param cq1
* @param cq2
* @return true if the first query is contained in the second query
*/
boolean isContainedIn(ImmutableCQ
cq1, ImmutableCQ
cq2);
ImmutableCollection> chaseAllAtoms(ImmutableCollection> atoms);
/***
* Removes queries that are contained syntactically, using the method
* isContainedIn(CQIE q1, CQIE 2).
*
* Removal of queries is done in two main double scans. The first scan goes
* top-down/down-top, the second scan goes down-top/top-down
*
* @param queries
*/
default void removeContainedQueries(List> queries) {
// first pass - from the start
{
Iterator> iterator = queries.iterator();
while (iterator.hasNext()) {
ImmutableCQ query = iterator.next();
ListIterator> iterator2 = queries.listIterator(queries.size());
while (iterator2.hasPrevious()) {
ImmutableCQ query2 = iterator2.previous();
if (query2 == query)
break;
if (isContainedIn(query, query2)) {
iterator.remove();
break;
}
}
}
}
// second pass - from the end
{
ListIterator> iterator = queries.listIterator(queries.size());
while (iterator.hasPrevious()) {
ImmutableCQ query = iterator.previous();
Iterator> iterator2 = queries.iterator();
while (iterator2.hasNext()) {
ImmutableCQ query2 = iterator2.next();
if (query2 == query)
break;
if (isContainedIn(query, query2)) {
iterator.remove();
break;
}
}
}
}
}
}