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