001    package net.sf.cpsolver.exam.criteria;
002    
003    import java.util.Set;
004    
005    import net.sf.cpsolver.exam.model.Exam;
006    import net.sf.cpsolver.exam.model.ExamModel;
007    import net.sf.cpsolver.exam.model.ExamPeriod;
008    import net.sf.cpsolver.exam.model.ExamPlacement;
009    import net.sf.cpsolver.exam.model.ExamRoom;
010    import net.sf.cpsolver.exam.model.ExamRoomPlacement;
011    import net.sf.cpsolver.ifs.util.DataProperties;
012    
013    /**
014     * Room penalty (penalty for using given rooms). I.e., sum of
015     * {@link ExamRoomPlacement#getPenalty(ExamPeriod)} of assigned rooms.
016     * <br><br>
017     * A weight for room penalty can be set by problem property
018     * Exams.RoomPreferenceWeight, or in the input xml file, property
019     * roomWeight).
020     * 
021     * <br>
022     * 
023     * @version ExamTT 1.2 (Examination Timetabling)<br>
024     *          Copyright (C) 2008 - 2012 Tomas Muller<br>
025     *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
026     *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
027     * <br>
028     *          This library is free software; you can redistribute it and/or modify
029     *          it under the terms of the GNU Lesser General Public License as
030     *          published by the Free Software Foundation; either version 3 of the
031     *          License, or (at your option) any later version. <br>
032     * <br>
033     *          This library is distributed in the hope that it will be useful, but
034     *          WITHOUT ANY WARRANTY; without even the implied warranty of
035     *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
036     *          Lesser General Public License for more details. <br>
037     * <br>
038     *          You should have received a copy of the GNU Lesser General Public
039     *          License along with this library; if not see
040     *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
041     */
042    public class RoomPenalty extends ExamCriterion {
043        
044        @Override
045        public String getWeightName() {
046            return "Exams.RoomWeight";
047        }
048        
049        @Override
050        public String getXmlWeightName() {
051            return "roomWeight";
052        }
053        
054        @Override
055        public double getWeightDefault(DataProperties config) {
056            return 0.1;
057        }
058        
059        @Override
060        public double getValue(ExamPlacement value, Set<ExamPlacement> conflicts) {
061            double penalty = 0.0;
062            if (value.getRoomPlacements() != null)
063                for (ExamRoomPlacement r : value.getRoomPlacements()) {
064                    penalty += r.getPenalty(value.getPeriod());
065                }
066            return penalty;
067        }
068        
069        private int getMinPenalty(ExamRoom r) {
070            int min = Integer.MAX_VALUE;
071            for (ExamPeriod p : ((ExamModel)getModel()).getPeriods()) {
072                if (r.isAvailable(p)) {
073                    min = Math.min(min, r.getPenalty(p));
074                }
075            }
076            return min;
077        }
078    
079        private int getMaxPenalty(ExamRoom r) {
080            int max = Integer.MIN_VALUE;
081            for (ExamPeriod p : ((ExamModel)getModel()).getPeriods()) {
082                if (r.isAvailable(p)) {
083                    max = Math.max(max, r.getPenalty(p));
084                }
085            }
086            return max;
087        }
088    
089        @Override
090        protected void computeBounds() {
091            iBounds = new double[] { 0.0, 0.0 };
092            for (Exam exam : getModel().variables()) {
093                if (!exam.getRoomPlacements().isEmpty()) {
094                    int minPenalty = Integer.MAX_VALUE, maxPenalty = Integer.MIN_VALUE;
095                    for (ExamRoomPlacement roomPlacement : exam.getRoomPlacements()) {
096                        minPenalty = Math.min(minPenalty, 2 * roomPlacement.getPenalty() + getMinPenalty(roomPlacement.getRoom()));
097                        maxPenalty = Math.max(maxPenalty, 2 * roomPlacement.getPenalty() + getMaxPenalty(roomPlacement.getRoom()));
098                    }
099                    iBounds[0] += minPenalty;
100                    iBounds[1] += maxPenalty;
101                }
102            }
103        }
104        
105        @Override
106        public String toString() {
107            return "RP:" + sDoubleFormat.format(getWeightedValue());
108        }
109    
110        @Override
111        public boolean isPeriodCriterion() { return false; }
112    }