/*
* Copyright 2012 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.optaplanner.examples.tsp.solver.score;
import org.optaplanner.core.api.score.buildin.simplelong.SimpleLongScore;
import org.optaplanner.core.impl.score.director.incremental.AbstractIncrementalScoreCalculator;
import org.optaplanner.examples.tsp.domain.Domicile;
import org.optaplanner.examples.tsp.domain.Standstill;
import org.optaplanner.examples.tsp.domain.TravelingSalesmanTour;
import org.optaplanner.examples.tsp.domain.Visit;
public class TspIncrementalScoreCalculator extends AbstractIncrementalScoreCalculator<TravelingSalesmanTour> {
private Domicile domicile;
private long score;
public void resetWorkingSolution(TravelingSalesmanTour tour) {
domicile = tour.getDomicile();
score = 0L;
for (Visit visit : tour.getVisitList()) {
insert(visit);
}
}
public void beforeEntityAdded(Object entity) {
// Do nothing
}
public void afterEntityAdded(Object entity) {
insert((Visit) entity);
}
public void beforeVariableChanged(Object entity, String variableName) {
retract((Visit) entity);
}
public void afterVariableChanged(Object entity, String variableName) {
insert((Visit) entity);
}
public void beforeEntityRemoved(Object entity) {
retract((Visit) entity);
}
public void afterEntityRemoved(Object entity) {
// Do nothing
}
private void insert(Visit visit) {
Standstill previousStandstill = visit.getPreviousStandstill();
if (previousStandstill != null) {
score -= visit.getDistanceFromPreviousStandstill();
// HACK: This counts too much, but the insert/retracts balance each other out
score += previousStandstill.getDistanceTo(domicile);
score -= visit.getDistanceTo(domicile);
}
}
private void retract(Visit visit) {
Standstill previousStandstill = visit.getPreviousStandstill();
if (previousStandstill != null) {
score += visit.getDistanceFromPreviousStandstill();
// HACK: This counts too much, but the insert/retracts balance each other out
score -= previousStandstill.getDistanceTo(domicile);
score += visit.getDistanceTo(domicile);
}
}
public SimpleLongScore calculateScore() {
return SimpleLongScore.valueOf(score);
}
}