    001package org.cpsolver.ifs.model;
    002
    003import java.util.Map;
    004
    005import org.cpsolver.ifs.assignment.Assignment;
    006
    007
    008/**
    009 * IFS neighbour.
    010 *
    011 * @see org.cpsolver.ifs.heuristics.NeighbourSelection
    012 *
    013 * @version IFS 1.3 (Iterative Forward Search)<br>
    014 *          Copyright (C) 2006 - 2014 Tomáš Müller<br>
    015 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    016 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    017 * <br>
    018 *          This library is free software; you can redistribute it and/or modify
    019 *          it under the terms of the GNU Lesser General Public License as
    020 *          published by the Free Software Foundation; either version 3 of the
    021 *          License, or (at your option) any later version. <br>
    022 * <br>
    023 *          This library is distributed in the hope that it will be useful, but
    024 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    025 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    026 *          Lesser General Public License for more details. <br>
    027 * <br>
    028 *          You should have received a copy of the GNU Lesser General Public
    029 *          License along with this library; if not see
    030 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    031 *
    032 * @param <V> Variable
    033 * @param <T> Value
    034 */
    035public interface Neighbour<V extends Variable<V, T>, T extends Value<V, T>> {
    036    /** Perform assignment
    037     * @param assignment current assignment
    038     * @param iteration current iteration
    039     **/
    040    public void assign(Assignment<V, T> assignment, long iteration);
    041
    042    /** Difference in the evaluation function, if this neighnour is assigned.
    043     * @param assignment current assignment
    044     * @return difference in the solution value when assigned
    045     **/
    046    public double value(Assignment<V, T> assignment);
    047
    048    /** Return assignments to be done.
    049     * @return list of assignments (including unassignments) of this neighbour
    050     **/
    051    public Map<V, T> assignments();
    052}