| /* |
| * Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code 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 |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * |
| * Driven by: 3GBZipFiles.sh |
| */ |
| |
| import java.io.RandomAccessFile; |
| import java.io.IOException; |
| import java.util.Random; |
| |
| public class FileBuilder { |
| private static void usageError() { |
| System.err.println("Usage: FileBuilder filetype filename filesize"); |
| System.err.println(""); |
| System.err.println("Makes a file named FILENAME of size FILESIZE."); |
| System.err.println("If FILETYPE is \"MostlyEmpty\", the file contents is mostly null bytes"); |
| System.err.println("(which might occupy no disk space if the right OS support exists)."); |
| System.err.println("If FILETYPE is \"SlightlyCompressible\", the file contents are"); |
| System.err.println("approximately 90% random data."); |
| System.exit(1); |
| } |
| |
| public static void main (String[] args) throws IOException { |
| if (args.length != 3) |
| usageError(); |
| String filetype = args[0]; |
| String filename = args[1]; |
| long filesize = Long.parseLong(args[2]); |
| |
| if (! (filetype.equals("MostlyEmpty") || |
| filetype.equals("SlightlyCompressible"))) |
| usageError(); |
| |
| try (RandomAccessFile raf = new RandomAccessFile(filename, "rw")) { |
| if (filetype.equals("SlightlyCompressible")) { |
| byte[] randomBytes = new byte[16384]; |
| byte[] nullBytes = new byte[randomBytes.length/10]; |
| Random rand = new Random(); |
| for (int i = 0; raf.length() < filesize; ++i) { |
| rand.nextBytes(randomBytes); |
| raf.write(nullBytes); |
| raf.write(randomBytes); |
| } |
| } |
| |
| // Make sure file is exactly the requested size, and that |
| // a unique identifying trailer is written. |
| byte[] filenameBytes = filename.getBytes("UTF8"); |
| raf.seek(filesize-filenameBytes.length); |
| raf.write(filenameBytes); |
| raf.setLength(filesize); |
| } |
| } |
| } |