显示磁盘空间信息，如df（1M）程序

import java.nio.file.*;//时 代 J     a    v  a - nowjava.com

import java.nio.file.attribute.*;

import java.io.IOException;


/**

 * Example utility that works like the df(1M) program to print out disk space

 * information

 */


public class DiskUsage {


    static final long K = 1024;


    static void printFileStore(FileStore store) throws IOException {

        long total = store.getTotalSpace() / K;

        long used = (store.getTotalSpace() - store.getUnallocatedSpace())

                / K;

        long avail = store.getUsableSpace() / K;


        String s = store.toString();

        if (s.length() > 20) {

            System.out.println(s);

            s = "";

        }

        System.out.format("%-20s %12d %12d %12d\n", s, total, used, avail);/*来 自 NowJava.com - 时代Java*/

    }


    public static void main(String[] args) throws IOException {

        System.out.format("%-20s %12s %12s %12s\n", "Filesystem", "kbytes",

                "used", "avail");

        if (args.length == 0) {

            FileSystem fs = FileSystems.getDefault();

            for (FileStore store : fs.getFileStores()) {

                printFileStore(store);

            }

        } else {

            for (String file : args) {

                FileStore store = Files.getFileStore(Paths.get(file));

                printFileStore(store);

            }

        }

    }

}