001    package net.sf.cpsolver.exam.criteria;
002    
003    import java.util.Collection;
004    import java.util.Set;
005    
006    import net.sf.cpsolver.exam.criteria.additional.RoomViolation;
007    import net.sf.cpsolver.exam.model.Exam;
008    import net.sf.cpsolver.exam.model.ExamModel;
009    import net.sf.cpsolver.exam.model.ExamPeriod;
010    import net.sf.cpsolver.exam.model.ExamPlacement;
011    import net.sf.cpsolver.exam.model.ExamRoom;
012    import net.sf.cpsolver.exam.model.ExamRoomPlacement;
013    import net.sf.cpsolver.ifs.solver.Solver;
014    import net.sf.cpsolver.ifs.util.DataProperties;
015    
016    /**
017     * Room penalty (penalty for using given rooms). I.e., sum of
018     * {@link ExamRoomPlacement#getPenalty(ExamPeriod)} of assigned rooms.
019     * <br><br>
020     * A weight for room penalty can be set by problem property
021     * Exams.RoomPreferenceWeight, or in the input xml file, property
022     * roomWeight).
023     * 
024     * <br>
025     * 
026     * @version ExamTT 1.2 (Examination Timetabling)<br>
027     *          Copyright (C) 2008 - 2012 Tomas Muller<br>
028     *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
029     *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
030     * <br>
031     *          This library is free software; you can redistribute it and/or modify
032     *          it under the terms of the GNU Lesser General Public License as
033     *          published by the Free Software Foundation; either version 3 of the
034     *          License, or (at your option) any later version. <br>
035     * <br>
036     *          This library is distributed in the hope that it will be useful, but
037     *          WITHOUT ANY WARRANTY; without even the implied warranty of
038     *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
039     *          Lesser General Public License for more details. <br>
040     * <br>
041     *          You should have received a copy of the GNU Lesser General Public
042     *          License along with this library; if not see
043     *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
044     */
045    public class RoomPenalty extends ExamCriterion {
046        protected Integer iSoftRooms = null;
047        
048        @Override
049        public boolean init(Solver<Exam, ExamPlacement> solver) {
050            if (super.init(solver)) {
051                iSoftRooms = solver.getProperties().getPropertyInteger("Exam.SoftRooms", null);
052                if (iSoftRooms != null) {
053                    RoomViolation rv = new RoomViolation();
054                    getModel().addCriterion(rv);
055                    return rv.init(solver);
056                }
057            }
058            return true;
059        }
060        
061        @Override
062        public String getWeightName() {
063            return "Exams.RoomWeight";
064        }
065        
066        @Override
067        public String getXmlWeightName() {
068            return "roomWeight";
069        }
070        
071        @Override
072        public double getWeightDefault(DataProperties config) {
073            return 0.1;
074        }
075        
076        @Override
077        public double getValue(ExamPlacement value, Set<ExamPlacement> conflicts) {
078            double penalty = 0.0;
079            if (value.getRoomPlacements() != null)
080                for (ExamRoomPlacement r : value.getRoomPlacements()) {
081                    penalty += (iSoftRooms != null && (iSoftRooms == r.getPenalty() || iSoftRooms == r.getPenalty(value.getPeriod())) ? 0.0 : r.getPenalty(value.getPeriod()));
082                }
083            return penalty;
084        }
085        
086        private int getMinPenalty(ExamRoom r) {
087            int min = Integer.MAX_VALUE;
088            for (ExamPeriod p : ((ExamModel)getModel()).getPeriods()) {
089                if (r.isAvailable(p) && (iSoftRooms == null || r.getPenalty(p) != iSoftRooms)) {
090                    min = Math.min(min, r.getPenalty(p));
091                }
092            }
093            return min;
094        }
095    
096        private int getMaxPenalty(ExamRoom r) {
097            int max = Integer.MIN_VALUE;
098            for (ExamPeriod p : ((ExamModel)getModel()).getPeriods()) {
099                if (r.isAvailable(p) && (iSoftRooms == null || r.getPenalty(p) != iSoftRooms)) {
100                    max = Math.max(max, r.getPenalty(p));
101                }
102            }
103            return max;
104        }
105        
106        private boolean isAvailable(ExamRoom r) {
107            for (ExamPeriod p : ((ExamModel)getModel()).getPeriods()) {
108                if (r.isAvailable(p) && (iSoftRooms == null || r.getPenalty(p) != iSoftRooms))
109                    return true;
110            }
111            return false;
112        }
113    
114        @Override
115        public double[] getBounds(Collection<Exam> variables) {
116            double[] bounds = new double[] { 0.0, 0.0 };
117            for (Exam exam : variables) {
118                if (!exam.getRoomPlacements().isEmpty()) {
119                    int minPenalty = Integer.MAX_VALUE, maxPenalty = Integer.MIN_VALUE;
120                    for (ExamRoomPlacement roomPlacement : exam.getRoomPlacements()) {
121                        if (iSoftRooms != null && iSoftRooms == roomPlacement.getPenalty()) continue;
122                        if (!isAvailable(roomPlacement.getRoom())) continue;
123                        minPenalty = Math.min(minPenalty, 2 * roomPlacement.getPenalty() + getMinPenalty(roomPlacement.getRoom()));
124                        maxPenalty = Math.max(maxPenalty, 2 * roomPlacement.getPenalty() + getMaxPenalty(roomPlacement.getRoom()));
125                    }
126                    bounds[0] += minPenalty;
127                    bounds[1] += maxPenalty;
128                }
129            }
130            return bounds;
131        }
132        
133        @Override
134        public String toString() {
135            return "RP:" + sDoubleFormat.format(getValue());
136        }
137    
138        @Override
139        public boolean isPeriodCriterion() { return false; }
140    }