Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 *   This program is 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, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   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, see <http://www.gnu.org/licenses/>.
 */

public class Main {
    /** whether to use all available cores. */
    public final static int ALL = -1;
    /** the number of threads used to be considered sequential. */
    public final static int SEQUENTIAL = 1;

    /**
     * Calculates the number of threads to use.
     *
     * @param numThreads        the requested number of threads (-1 for # of cores/cpus)
     * @param maxThreads        the maximum to ask for
     * @return                  the actual number of threads to use, (1 = single thread)
     */
    public static int getActualNumThreads(int numThreads, int maxThreads) {
        int result;

        if (numThreads == ALL)
            result = getAvailableProcessors();
        else if (numThreads > SEQUENTIAL)
            result = Math.min(numThreads, maxThreads);
        else
            result = SEQUENTIAL;
        if (result > getAvailableProcessors())
            result = getAvailableProcessors();

        return result;
    }

    /**
     * Returns the available number of processors on the machine.
     *
     * @return                  the number of processors
     */
    public static int getAvailableProcessors() {
        return Runtime.getRuntime().availableProcessors();
    }
}