jdk/src/sample/share/nio/file/DiskUsage.java

/*
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 *
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 * modification, are permitted provided that the following conditions
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 *
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 *     notice, this list of conditions and the following disclaimer.
 *
 *   - Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
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 *
 *   - Neither the name of Oracle nor the names of its
 *     contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
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/*
 * This source code is provided to illustrate the usage of a given feature
 * or technique and has been deliberately simplified. Additional steps
 * required for a production-quality application, such as security checks,
 * input validation and proper error handling, might not be present in
 * this sample code.
 */


import java.nio.file.*;
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);
    }

    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);
            }
        }
    }
}