1 /*
   2  * Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /**
  25  * @test
  26  * @bug 4844847
  27  * @summary Test the MessageDigest.update(ByteBuffer) method
  28  * @author Andreas Sterbenz
  29  */
  30 
  31 import java.util.*;
  32 import java.nio.*;
  33 
  34 import java.security.*;
  35 
  36 public class ByteBuffers {
  37 
  38     public static void main(String[] args) throws Exception {
  39         Provider p = Security.getProvider("SUN");
  40         Random random = new Random();
  41         int n = 10 * 1024;
  42         byte[] t = new byte[n];
  43         random.nextBytes(t);
  44 
  45         MessageDigest md = MessageDigest.getInstance("MD5", p);
  46         byte[] d1 = md.digest(t);
  47 
  48         // test 1: ByteBuffer with an accessible backing array
  49         ByteBuffer b1 = ByteBuffer.allocate(n + 256);
  50         b1.position(random.nextInt(256));
  51         b1.limit(b1.position() + n);
  52         ByteBuffer b2 = b1.slice();
  53         b2.put(t);
  54         b2.clear();
  55         byte[] d2 = digest(md, b2, random);
  56         if (Arrays.equals(d1, d2) == false) {
  57             throw new Exception("Test 1 failed");
  58         }
  59 
  60         // test 2: direct ByteBuffer
  61         ByteBuffer b3 = ByteBuffer.allocateDirect(t.length);
  62         b3.put(t);
  63         b3.clear();
  64         byte[] d3 = digest(md, b3, random);
  65         if (Arrays.equals(d1, d3) == false) {
  66             throw new Exception("Test 2 failed");
  67         }
  68 
  69         // test 3: ByteBuffer without an accessible backing array
  70         b2.clear();
  71         ByteBuffer b4 = b2.asReadOnlyBuffer();
  72         byte[] d4 = digest(md, b4, random);
  73         if (Arrays.equals(d1, d4) == false) {
  74             throw new Exception("Test 3 failed");
  75         }
  76         System.out.println("All tests passed");
  77     }
  78 
  79     private static byte[] digest(MessageDigest md, ByteBuffer b, Random random) throws Exception {
  80         int lim = b.limit();
  81         b.limit(random.nextInt(lim));
  82         md.update(b);
  83         if (b.hasRemaining()) {
  84             throw new Exception("Buffer not consumed");
  85         }
  86         b.limit(lim);
  87         md.update(b);
  88         if (b.hasRemaining()) {
  89             throw new Exception("Buffer not consumed");
  90         }
  91         return md.digest();
  92     }
  93 }