    001package org.cpsolver.coursett.criteria.placement;
    002
    003import java.util.HashMap;
    004import java.util.Map;
    005import java.util.Set;
    006
    007import org.cpsolver.coursett.model.Lecture;
    008import org.cpsolver.coursett.model.Placement;
    009import org.cpsolver.ifs.assignment.Assignment;
    010import org.cpsolver.ifs.util.Counter;
    011
    012
    013/**
    014 * Count number of past assignments of a value. Avoid repetition by penalizing
    015 * values that have been assigned too many times already.
    016 * <br>
    017 *
    018 * @author  Tomáš Müller
    019 * @version CourseTT 1.3 (University Course Timetabling)<br>
    020 *          Copyright (C) 2006 - 2014 Tomáš Müller<br>
    021 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    022 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    023 * <br>
    024 *          This library is free software; you can redistribute it and/or modify
    025 *          it under the terms of the GNU Lesser General Public License as
    026 *          published by the Free Software Foundation; either version 3 of the
    027 *          License, or (at your option) any later version. <br>
    028 * <br>
    029 *          This library is distributed in the hope that it will be useful, but
    030 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    031 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    032 *          Lesser General Public License for more details. <br>
    033 * <br>
    034 *          You should have received a copy of the GNU Lesser General Public
    035 *          License along with this library; if not see
    036 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    037 */
    038@Deprecated
    039public class AssignmentCount extends PlacementSelectionCriterion {
    040
    041    public AssignmentCount() {
    042        setValueUpdateType(ValueUpdateType.BeforeUnassignedAfterAssigned);
    043    }
    044
    045    @Override
    046    public String getPlacementSelectionWeightName() {
    047        return "Placement.NrAssignmentsWeight";
    048    }
    049
    050    @Override
    051    public double getValue(Assignment<Lecture, Placement> assignment, Placement value, Set<Placement> conflicts) {
    052        return ((AssignmentCountContext)getContext(assignment)).countAssignments(value);
    053    }
    054
    055    @Override
    056    public ValueContext createAssignmentContext(Assignment<Lecture, Placement> assignment) {
    057        return new AssignmentCountContext(assignment);
    058    }
    059
    060    public class AssignmentCountContext extends ValueContext {
    061        Map<Placement, Counter> iCounter = new HashMap<Placement, Counter>();
    062
    063        protected AssignmentCountContext(Assignment<Lecture, Placement> assignment) {
    064            super(assignment);
    065        }
    066
    067        @Override
    068        protected void assigned(Assignment<Lecture, Placement> assignment, Placement value) {
    069            Counter c = iCounter.get(value);
    070            if (c == null) {
    071                c = new Counter();
    072                iCounter.put(value, c);
    073            }
    074            c.inc(1);
    075        }
    076
    077        @Override
    078        protected void unassigned(Assignment<Lecture, Placement> assignment, Placement value) {
    079        }
    080
    081        public long countAssignments(Placement value) {
    082            Counter c = iCounter.get(value);
    083            return c == null ? 0 : c.get();
    084        }
    085    }
    086}