Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * This file is part of OpenVPN-Settings.
 *
 * Copyright  2009-2012  Friedrich Schuffelhut
 *
 * OpenVPN-Settings 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.
 *
 * OpenVPN-Settings 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 OpenVPN-Settings.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Report bugs or new features at: http://code.google.com/p/android-openvpn-settings/
 * Contact the author at:          android.openvpn@schaeuffelhut.de
 */

import java.io.File;

public class Main {
    /**
     * Returns the size of the specified file or directory. If the provided 
     * {@link File} is a regular file, then the file's length is returned.
     * If the argument is a directory, then the size of the directory is
     * calculated recursively. If a directory or subdirectory is security 
     * restricted, its size will not be included.
     * 
     * @param file the regular file or directory to return the size 
     *        of (must not be <code>null</code>).
     * 
     * @return the length of the file, or recursive size of the directory, 
     *         provided (in bytes).
     * 
     * @throws NullPointerException if the file is <code>null</code>
     * @throws IllegalArgumentException if the file does not exist.
     *         
     * @since Commons IO 2.0
     */
    public static long sizeOf(File file) {

        if (!file.exists()) {
            String message = file + " does not exist";
            throw new IllegalArgumentException(message);
        }

        if (file.isDirectory()) {
            return sizeOfDirectory(file);
        } else {
            return file.length();
        }

    }

    /**
     * Counts the size of a directory recursively (sum of the length of all files).
     *
     * @param directory  directory to inspect, must not be <code>null</code>
     * @return size of directory in bytes, 0 if directory is security restricted
     * @throws NullPointerException if the directory is <code>null</code>
     */
    public static long sizeOfDirectory(File directory) {
        if (!directory.exists()) {
            String message = directory + " does not exist";
            throw new IllegalArgumentException(message);
        }

        if (!directory.isDirectory()) {
            String message = directory + " is not a directory";
            throw new IllegalArgumentException(message);
        }

        long size = 0;

        File[] files = directory.listFiles();
        if (files == null) { // null if security restricted
            return 0L;
        }
        for (File file : files) {
            size += sizeOf(file);
        }

        return size;
    }
}