package de.lmu.ifi.dbs.elki.database.query.distance;
/*
This file is part of ELKI:
Environment for Developing KDD-Applications Supported by Index-Structures
Copyright (C) 2013
Ludwig-Maximilians-Universität München
Lehr- und Forschungseinheit für Datenbanksysteme
ELKI Development Team
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Affero General Public License for more details.
You should have received a copy of the GNU Affero General Public License
along with this program. If not, see .
*/
import de.lmu.ifi.dbs.elki.database.ids.DBIDRef;
import de.lmu.ifi.dbs.elki.database.relation.Relation;
import de.lmu.ifi.dbs.elki.distance.distancefunction.PrimitiveDistanceFunction;
import de.lmu.ifi.dbs.elki.distance.distancevalue.Distance;
/**
* Run a database query in a database context.
*
* @author Erich Schubert
*
* @apiviz.landmark
* @apiviz.uses PrimitiveDistanceFunction
*
* @param Database object type.
* @param Distance result type.
*/
public class PrimitiveDistanceQuery> extends AbstractDistanceQuery {
/**
* The distance function we use.
*/
final protected PrimitiveDistanceFunction super O, D> distanceFunction;
/**
* Constructor.
*
* @param relation Representation to use.
* @param distanceFunction Our distance function
*/
public PrimitiveDistanceQuery(Relation extends O> relation, PrimitiveDistanceFunction super O, D> distanceFunction) {
super(relation);
this.distanceFunction = distanceFunction;
}
@Override
public D distance(DBIDRef id1, DBIDRef id2) {
O o1 = relation.get(id1);
O o2 = relation.get(id2);
return distance(o1, o2);
}
@Override
public D distance(O o1, DBIDRef id2) {
O o2 = relation.get(id2);
return distance(o1, o2);
}
@Override
public D distance(DBIDRef id1, O o2) {
O o1 = relation.get(id1);
return distance(o1, o2);
}
@Override
public D distance(O o1, O o2) {
if(o1 == null) {
throw new UnsupportedOperationException("This distance function can only be used for object instances.");
}
if(o2 == null) {
throw new UnsupportedOperationException("This distance function can only be used for object instances.");
}
return distanceFunction.distance(o1, o2);
}
@Override
public PrimitiveDistanceFunction super O, D> getDistanceFunction() {
return distanceFunction;
}
}