Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (C) 2012 www.amsoft.cn
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.io.File;
import java.io.FileFilter;

import java.util.regex.Pattern;

public class Main {
    /**
     * Gets the number of cores available in this device, across all processors.
     * Requires: Ability to peruse the filesystem at "/sys/devices/system/cpu"
     *
     * @return The number of cores, or 1 if failed to get result
     */
    public static int getNumCores() {
        try {
            //Get directory containing CPU info 
            File dir = new File("/sys/devices/system/cpu/");
            //Filter to only list the devices we care about 
            File[] files = dir.listFiles(new FileFilter() {

                @Override
                public boolean accept(File pathname) {
                    //Check if filename is "cpu", followed by a single digit number 
                    return Pattern.matches("cpu[0-9]", pathname.getName());
                }

            });
            //Return the number of cores (virtual CPU devices) 
            if (files != null)
                return files.length;
            return 1;
        } catch (Exception e) {
            e.printStackTrace();
            return 1;
        }
    }
}