001package org.cpsolver.coursett.model;
002
003import java.util.Collection;
004
005import org.cpsolver.ifs.assignment.Assignment;
006import org.cpsolver.ifs.solution.Solution;
007import org.cpsolver.ifs.termination.TerminationCondition;
008
009
010/**
011 * Interface for student sectioning functions needed within the course timetabling solver.<br>
012 * <br>
013 * Many course offerings consist of multiple classes, with students enrolled in
014 * the course divided among them. These classes are often linked by a set of
015 * constraints, namely:
016 * <ul>
017 * <li>Each class has a limit stating the maximum number of students who can be
018 * enrolled in it.
019 * <li>A student must be enrolled in exactly one class for each subpart of a
020 * course.
021 * <li>If two subparts of a course have a parent-child relationship, a student
022 * enrolled in the parent class must also be enrolled in one of the child
023 * classes.
024 * </ul>
025 * Moreover, some of the classes of an offering may be required or prohibited
026 * for certain students, based on reservations that can be set on an offering, a
027 * configuration, or a class. <br>
028 * While the data are loaded into the solver, an initial sectioning of students into
029 * classes is processed (see {@link InitialSectioning}). However, it
030 * is still possible to improve on the number of student conflicts in the
031 * solution. This can be accomplished by moving students between alternative
032 * classes of the same course during or after the search (see
033 * {@link FinalSectioning}).
034 * 
035 * @author  Tomáš Müller
036 * @version CourseTT 1.3 (University Course Timetabling)<br>
037 *          Copyright (C) 2014 Tomáš Müller<br>
038 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
039 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
040 * <br>
041 *          This library is free software; you can redistribute it and/or modify
042 *          it under the terms of the GNU Lesser General Public License as
043 *          published by the Free Software Foundation; either version 3 of the
044 *          License, or (at your option) any later version. <br>
045 * <br>
046 *          This library is distributed in the hope that it will be useful, but
047 *          WITHOUT ANY WARRANTY; without even the implied warranty of
048 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
049 *          Lesser General Public License for more details. <br>
050 * <br>
051 *          You should have received a copy of the GNU Lesser General Public
052 *          License along with this library; if not see
053 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
054 */
055public interface StudentSectioning {
056
057    /**
058     * Enroll students into the given offering during the initial data load.
059     * @param assignment current assignment
060     * @param offeringId instructional offering id
061     * @param courseName course name
062     * @param students list of students to be sectioned
063     * @param configurations list of configurations the students are to be sectioned into
064     */
065    public void initialSectioning(Assignment<Lecture, Placement> assignment, Long offeringId, String courseName, Collection<Student> students, Collection<Configuration> configurations);
066    
067    /**
068     * Return true if final student sectioning is implemented. 
069     * @return true if final student sectioning is implemented
070     */
071    public boolean hasFinalSectioning();
072    
073    /**
074     * Run student final sectioning (switching students between sections of the same
075     * class in order to minimize overall number of student conflicts).
076     * @param solution current solution
077     * @param termination termination condition (optional)
078     */
079    public void switchStudents(Solution<Lecture, Placement> solution, TerminationCondition<Lecture, Placement> termination);
080    
081    /**
082     * Perform sectioning on the given lecture
083     * @param assignment current assignment
084     * @param lecture given lecture
085     * @param recursive recursively resection lectures affected by a student swap
086     * @param configAsWell resection students between configurations as well
087     **/
088    public void resection(Assignment<Lecture, Placement> assignment, Lecture lecture, boolean recursive, boolean configAsWell);
089}