com.github.tkurz.sparqlmm.function.spatial.relation.directional.BelowFunction Maven / Gradle / Ivy
package com.github.tkurz.sparqlmm.function.spatial.relation.directional;
import com.github.tkurz.media.ontology.function.SpatialFunction;
import com.github.tkurz.media.ontology.type.SpatialEntity;
import com.github.tkurz.sparqlmm.Constants;
import com.github.tkurz.sparqlmm.doc.FunctionDoc;
import com.github.tkurz.sparqlmm.utils.FunctionHelper;
import org.openrdf.model.Value;
import org.openrdf.model.ValueFactory;
import org.openrdf.query.algebra.evaluation.ValueExprEvaluationException;
import org.openrdf.query.algebra.evaluation.function.Function;
/**
* ...
*
* Author: Thomas Kurz ([email protected])
*/
@FunctionDoc(title = "below", properties = {SpatialEntity.class, SpatialEntity.class}, reference = FunctionDoc.Reference.spatial, description = "returns true p1 if is below p2 (based on model m), else false.")
public class BelowFunction implements Function {
/**
* return the URI
*/
public String getURI() {
return Constants.NAMESPACE + "below";
}
@Override
public Value evaluate(ValueFactory valueFactory, Value... values) throws ValueExprEvaluationException {
try {
//check preconditions
if(values.length != 2 || !FunctionHelper.isComparable(values)) return FunctionHelper.BOOL_LITERAL_FALSE;
//check if values are correct
SpatialEntity[] entities = FunctionHelper.toSpatialEntities(values);
//evaluate
return valueFactory.createLiteral(SpatialFunction.DirectionalFunction.below(entities[0], entities[1]));
} catch (IllegalArgumentException e) {
return FunctionHelper.BOOL_LITERAL_FALSE;
}
}
}