SolvingStatistics.java

/*
 * Copyright (c) Fabien Hermenier
 *
 *        This file is part of Entropy.
 *
 *        Entropy is free software: you can redistribute it and/or modify
 *        it under the terms of the GNU Lesser General Public License as published by
 *        the Free Software Foundation, either version 3 of the License, or
 *        (at your option) any later version.
 *
 *        Entropy is distributed in the hope that it will be useful,
 *        but WITHOUT ANY WARRANTY; without even the implied warranty of
 *        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *        GNU Lesser General Public License for more details.
 *
 *        You should have received a copy of the GNU Lesser General Public License
 *        along with Entropy.  If not, see <http://www.gnu.org/licenses/>.
 */

package entropy.plan;

/**
 * Statistics about the solving process of a RP.
 *
 * @author Fabien Hermenier
 */
public class SolvingStatistics implements Cloneable {

    private static SolvingStatistics noStats = new SolvingStatistics(0, 0, 0, false);

    /**
     * The number of opened nodes.
     */
    private int nbNodes;

    /**
     * The number of backtracks.
     */
    private int nbBacktracks;

    /**
     * The moment the solution was computed.
     */
    private int timeCount;

    /**
     * Indicates whether or not the solver has hit the timeout.
     */
    private boolean timeout;

    /**
     * Make new statistics
     *
     * @param nbNodes      the number of opened nodes
     * @param nbBacktracks the number of backtracks
     * @param timeCount    the timeCount of the solution
     */
    public SolvingStatistics(int nbNodes, int nbBacktracks, int timeCount, boolean timeout) {
        this.nbNodes = nbNodes;
        this.nbBacktracks = nbBacktracks;
        this.timeCount = timeCount;
    }

    /**
     * @return the number of opened nodes.
     */
    public int getNbNodes() {
        return nbNodes;
    }

    /**
     * @return the number of backtracks.
     */
    public int getNbBacktracks() {
        return nbBacktracks;
    }

    /**
     * @return the moment the solution was computed.
     */
    public int getTimeCount() {
        return timeCount;
    }

    public boolean hasReachedTimeout() {
        return this.timeout;
    }

    @Override
    public String toString() {
        return new StringBuilder("nodes=").append(nbNodes)
                .append(", backtracks=").append(nbBacktracks)
                .append(", time=").append(timeCount)
                .append(", timeout=").append(timeout).toString();
    }

    /**
     * Export data to a String that sump up the solution. Parseable data
     * Fields are separated by space. First is the objective, second the number of
     * opened nodes, third is the number of backtracks. Last is the time then the timeout
     *
     * @return a String
     */
    public String toRawData() {
        return new StringBuilder().append(nbNodes)
                .append(' ').append(nbBacktracks)
                .append(' ').append(timeCount)
                .append(' ').append(timeout ? 1 : 0).toString();
    }

    public static String noResults() {
        return "- - - -";
    }

    public static final SolvingStatistics getStatisticsForNotSolvingProcess() {
        return noStats;
    }

    @Override
    public SolvingStatistics clone() {
        return new SolvingStatistics(nbNodes, nbBacktracks, timeCount, timeout);
    }
}