001package org.cpsolver.instructor.model;
002
003import org.cpsolver.coursett.Constants;
004
005/**
006 * A preference. This class encapsulates a time, course, instructor, or attribute preference.
007 * 
008 * @version IFS 1.3 (Instructor Sectioning)<br>
009 *          Copyright (C) 2016 Tomáš Müller<br>
010 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
011 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
012 * <br>
013 *          This library is free software; you can redistribute it and/or modify
014 *          it under the terms of the GNU Lesser General Public License as
015 *          published by the Free Software Foundation; either version 3 of the
016 *          License, or (at your option) any later version. <br>
017 * <br>
018 *          This library is distributed in the hope that it will be useful, but
019 *          WITHOUT ANY WARRANTY; without even the implied warranty of
020 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
021 *          Lesser General Public License for more details. <br>
022 * <br>
023 *          You should have received a copy of the GNU Lesser General Public
024 *          License along with this library; if not see
025 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
026 */
027public class Preference<T> {
028    protected T iTarget;
029    protected int iPreference;
030
031    /**
032     * Constructor
033     * @param target object for which the preference is given
034     * @param preference preference value
035     */
036    public Preference(T target, int preference) {
037        iTarget = target;
038        iPreference = preference;
039    }
040    
041    /**
042     * Is required?
043     * @return true if the preference is required
044     */
045    public boolean isRequired() { return iPreference < Constants.sPreferenceLevelRequired / 2; }
046
047    /**
048     * Is prohibited?
049     * @return true if the preference is prohibited
050     */
051    public boolean isProhibited() { return iPreference > Constants.sPreferenceLevelProhibited / 2; }
052    
053    /**
054     * Preference value
055     * @return preference value
056     */
057    public int getPreference() { return iPreference; }
058    
059    /**
060     * Target object for which the preference is given
061     * @return target
062     */
063    public T getTarget() { return iTarget; }
064    
065    @Override
066    public String toString() { return getTarget() + ": " + (isRequired() ? "R" : isProhibited() ? "P" : getPreference()); }
067}