    001package net.sf.cpsolver.exam.criteria;
    002
    003import java.util.Collection;
    004import java.util.Set;
    005
    006import net.sf.cpsolver.exam.criteria.additional.PeriodViolation;
    007import net.sf.cpsolver.exam.model.Exam;
    008import net.sf.cpsolver.exam.model.ExamPeriodPlacement;
    009import net.sf.cpsolver.exam.model.ExamPlacement;
    010import net.sf.cpsolver.ifs.solver.Solver;
    011import net.sf.cpsolver.ifs.util.DataProperties;
    012
    013/**
    014 * Cost for using a period. See {@link ExamPeriodPlacement#getPenalty()} for more details.
    015 * <br><br>
    016 * A weight for period penalty can be set by problem property
    017 * Exams.PeriodWeight, or in the input xml file, property periodWeight.
    018 *
    019 * <br>
    020 *
    021 * @version ExamTT 1.2 (Examination Timetabling)<br>
    022 *          Copyright (C) 2008 - 2012 Tomáš Müller<br>
    023 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    024 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    025 * <br>
    026 *          This library is free software; you can redistribute it and/or modify
    027 *          it under the terms of the GNU Lesser General Public License as
    028 *          published by the Free Software Foundation; either version 3 of the
    029 *          License, or (at your option) any later version. <br>
    030 * <br>
    031 *          This library is distributed in the hope that it will be useful, but
    032 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    033 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    034 *          Lesser General Public License for more details. <br>
    035 * <br>
    036 *          You should have received a copy of the GNU Lesser General Public
    037 *          License along with this library; if not see
    038 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    039 */
    040public class PeriodPenalty extends ExamCriterion {
    041    protected Integer iSoftPeriods = null;
    042
    043    @Override
    044    public boolean init(Solver<Exam, ExamPlacement> solver) {
    045        if (super.init(solver)) {
    046            iSoftPeriods = solver.getProperties().getPropertyInteger("Exam.SoftPeriods", null);
    047            if (iSoftPeriods != null) {
    048                PeriodViolation pv = new PeriodViolation();
    049                getModel().addCriterion(pv);
    050                return pv.init(solver);
    051            }
    052        }
    053        return true;
    054    }
    055
    056    @Override
    057    public String getWeightName() {
    058        return "Exams.PeriodWeight";
    059    }
    060
    061    @Override
    062    public String getXmlWeightName() {
    063        return "periodWeight";
    064    }
    065
    066    @Override
    067    public double getWeightDefault(DataProperties config) {
    068        return 1.0;
    069    }
    070
    071    @Override
    072    public double getValue(ExamPlacement value, Set<ExamPlacement> conflicts) {
    073        return (iSoftPeriods == null || (value.getPeriodPlacement().getExamPenalty() != iSoftPeriods &&  value.getPeriodPlacement().getPeriod().getPenalty() != iSoftPeriods) ? value.getPeriodPlacement().getPenalty() : 0.0);
    074    }
    075
    076    @Override
    077    public double[] getBounds(Collection<Exam> variables) {
    078        double[] bounds = new double[] { 0.0, 0.0 };
    079        for (Exam exam : variables) {
    080            if (!exam.getPeriodPlacements().isEmpty()) {
    081                int minPenalty = Integer.MAX_VALUE, maxPenalty = Integer.MIN_VALUE;
    082                for (ExamPeriodPlacement periodPlacement : exam.getPeriodPlacements()) {
    083                    if (iSoftPeriods != null && (periodPlacement.getExamPenalty() == iSoftPeriods || periodPlacement.getPeriod().getPenalty() == iSoftPeriods)) continue;
    084                    minPenalty = Math.min(minPenalty, periodPlacement.getPenalty());
    085                    maxPenalty = Math.max(maxPenalty, periodPlacement.getPenalty());
    086                }
    087                bounds[0] += minPenalty;
    088                bounds[1] += maxPenalty;
    089            }
    090        }
    091        return bounds;
    092    }
    093
    094    @Override
    095    public String toString() {
    096        return "PP:" + sDoubleFormat.format(getValue());
    097    }
    098}