Util.java Source code

Introduction

Here is the source code for Util.java

Source

import java.util.Random;

/**
 * BeehiveZ is a business process model and instance management system.
 * Copyright (C) 2011  
 * Institute of Information System and Engineering, School of Software, Tsinghua University,
 * Beijing, China
 *
 * Contact: jintao05@gmail.com 
 *
 * This program is a free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation with the version of 2.
 *
 * 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */

/**
 * @author Tao Jin
 * 
 */

public class Util {

    // calculate the discrete uniform distribution
    // ret[0] stores the number user given
    // ret[1] stores the count of the corresponding number in ret[0] with the
    // same index
    // for some number, the count maybe 0.
    // the parameter validation must be finished in advance.
    public static long[][] getDiscreteUniformDistribution(int min, int max, long total) {
        Random rand = new Random(System.currentTimeMillis());
        int span = max - min + 1;
        long avg = total / span;
        long[][] ret = new long[2][span];

        if (avg >= 1) {
            long count = 0;
            for (int i = 0; i < span; i++) {
                ret[0][i] = min + i;
                ret[1][i] = avg;
                count += avg;
            }

            if (count < total) {
                avg = span / (total - count);
                int a = (int) avg;
                int k = 0;
                while (count < total) {
                    int i = rand.nextInt(span);
                    ret[1][a * k]++;
                    k++;
                    count++;
                }
            }
        } else {
            for (int i = 0; i < span; i++) {
                ret[0][i] = min + i;
            }
            long count = 0;
            avg = span / total;
            while (count < total) {
                long k = count * avg;
                int kk = (int) k;
                ret[1][kk] = 1;
                count++;
                // int i = rand.nextInt(span);
                // if (ret[1][i] == 0) {
                // ret[1][i] = 1;
                // count++;
                // }
            }
        }
        return ret;
    }

}