    001package org.cpsolver.ifs.example.csp;
    002
    003import java.util.ArrayList;
    004import java.util.List;
    005import java.util.Random;
    006
    007import org.cpsolver.ifs.model.Variable;
    008
    009
    010/**
    011 * CSP variable. <br>
    012 * <br>
    013 * This class only implements generation of variable's values (domain)
    014 *
    015 * @author  Tomáš Müller
    016 * @version IFS 1.3 (Iterative Forward Search)<br>
    017 *          Copyright (C) 2006 - 2014 Tomáš Müller<br>
    018 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    019 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    020 * <br>
    021 *          This library is free software; you can redistribute it and/or modify
    022 *          it under the terms of the GNU Lesser General Public License as
    023 *          published by the Free Software Foundation; either version 3 of the
    024 *          License, or (at your option) any later version. <br>
    025 * <br>
    026 *          This library is distributed in the hope that it will be useful, but
    027 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    028 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    029 *          Lesser General Public License for more details. <br>
    030 * <br>
    031 *          You should have received a copy of the GNU Lesser General Public
    032 *          License along with this library; if not see
    033 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    034 */
    035public class CSPVariable extends Variable<CSPVariable, CSPValue> {
    036    private int iKernelId = -1;
    037
    038    /**
    039     * Constructor
    040     * @param id variable id
    041     * @param domainSize
    042     *            number of values of the variable
    043     */
    044    public CSPVariable(int id, int domainSize) {
    045        this(id, domainSize, -1);
    046    }
    047
    048    /**
    049     * Constructor
    050     *
    051     * @param id variable id
    052     * @param domainSize
    053     *            number of values of the variable
    054     * @param kernelId
    055     *            kernel id (for structured CSP)
    056     */
    057    public CSPVariable(int id, int domainSize, int kernelId) {
    058        super(null);
    059        iId = id;
    060        iKernelId = kernelId;
    061        setValues(computeValues(domainSize));
    062    }
    063
    064    /** Get kernel id
    065     * @return kernel id
    066     **/
    067    public int getKernelId() {
    068        return iKernelId;
    069    }
    070
    071    /**
    072     * Generate an intial value (for MPP and for forcing of existance of a
    073     * solution)
    074     * @param rnd random number generator
    075     */
    076    public void generateInitialValue(Random rnd) {
    077        CSPValue aValue = values(null).get((int) (rnd.nextFloat() * values(null).size()));
    078        setInitialAssignment(aValue);
    079    }
    080
    081    private List<CSPValue> computeValues(int domainSize) {
    082        List<CSPValue> values = new ArrayList<CSPValue>();
    083        for (int i = 0; i < domainSize; i++) {
    084            CSPValue value = new CSPValue(this, i);
    085            values.add(value);
    086        }
    087        return values;
    088    }
    089
    090    @Override
    091    public String getName() {
    092        return "V" + getId();
    093    }
    094}