lineardistributioninitializer.java

peersim最新版1.0.4

/*
 * Copyright (c) 2003-2005 The BISON Project
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License version 2 as
 * published by the Free Software Foundation.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 */

package example.loadbalance;

import peersim.config.*;
import peersim.core.*;
import peersim.vector.SingleValue;

/**
 * This class provides a simple linear distribution in a bounded interval
 * defined by {@link #PAR_MIN} and {@link #PAR_MAX} parameters. It is assumed
 * that the network nodes comply to the {@link peersim.vector.SingleValue}
 * interface.
 * 
 */
public class LinearDistributionInitializer implements Control {

    // ------------------------------------------------------------------------
    // Parameters
    // ------------------------------------------------------------------------

    /**
     * The upper bound of the values.
     * 
     * @config
     */
    private static final String PAR_MAX = "max";

    /**
     * The lower bound of the values. Defaults to -max.
     * 
     * @config
     */
    private static final String PAR_MIN = "min";

    /**
     * The protocol to operate on.
     * 
     * @config
     */
    private static final String PAR_PROT = "protocol";

    // ------------------------------------------------------------------------
    // Fields
    // ------------------------------------------------------------------------
    
    /** Maximum interval value,
    obtained from config property {@link #PAR_MAX}. */
    private final double max;

    /** Manimum interval value,
    obtained from config property {@link #PAR_MIN}. */
    private final double min;

    /** Protocol identifier, obtained from config property {@link #PAR_PROT}. */
    private final int protocolID;

    // ------------------------------------------------------------------------
    // Initialization
    // ------------------------------------------------------------------------
    /**
     * Standard constructor that reads the configuration parameters. Invoked by
     * the simulation engine.
     * 
     * @param prefix
     *            the configuration prefix for this class.
     */
    public LinearDistributionInitializer(String prefix) {
        max = Configuration.getDouble(prefix + "." + PAR_MAX);
        min = Configuration.getDouble(prefix + "." + PAR_MIN, -max);
        protocolID = Configuration.getPid(prefix + "." + PAR_PROT);
    }

    // ------------------------------------------------------------------------
    // Methods
    // ------------------------------------------------------------------------

    /**
    * This class provides a simple linear distribution in a bounded interval
    * defined by parameters {@link #PAR_MIN} and {@link #PAR_MAX}.
    */
    public boolean execute() {
        double step = (max - min) / (Network.size() - 1);
        double sum = 0.0;
        double tmp;
        for (int i = 0; i < Network.size(); ++i) {
            tmp = i * step + min;
            sum += tmp;
            ((SingleValue) Network.get(i).getProtocol(protocolID))
                    .setValue(tmp);
        }
        return false;
    }

}