2 * Copyright (C) 2007-2012 Argeo GmbH
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
8 * http://www.apache.org/licenses/LICENSE-2.0
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
16 package org
.argeo
.util
;
19 import java
.io
.FileInputStream
;
20 import java
.io
.IOException
;
21 import java
.io
.InputStream
;
22 import java
.nio
.ByteBuffer
;
23 import java
.nio
.channels
.FileChannel
;
24 import java
.security
.MessageDigest
;
25 import java
.security
.NoSuchAlgorithmException
;
27 /** Utilities around cryptographic digests */
28 public class DigestUtils
{
29 private static Boolean debug
= true;
30 // TODO: make it writable
31 private final static Integer byteBufferCapacity
= 100 * 1024;// 100 KB
33 public static String
digest(String algorithm
, byte[] bytes
) {
35 MessageDigest digest
= MessageDigest
.getInstance(algorithm
);
37 byte[] checksum
= digest
.digest();
38 String res
= encodeHexString(checksum
);
40 } catch (Exception e
) {
41 throw new UtilsException("Cannot digest with algorithm " + algorithm
, e
);
45 public static String
digest(String algorithm
, InputStream in
) {
47 MessageDigest digest
= MessageDigest
.getInstance(algorithm
);
48 // ReadableByteChannel channel = Channels.newChannel(in);
49 // ByteBuffer bb = ByteBuffer.allocateDirect(byteBufferCapacity);
50 // while (channel.read(bb) > 0)
52 byte[] buffer
= new byte[byteBufferCapacity
];
54 while ((read
= in
.read(buffer
)) > 0) {
55 digest
.update(buffer
, 0, read
);
58 byte[] checksum
= digest
.digest();
59 String res
= encodeHexString(checksum
);
61 } catch (Exception e
) {
62 throw new UtilsException("Cannot digest with algorithm " + algorithm
, e
);
64 StreamUtils
.closeQuietly(in
);
68 public static String
digest(String algorithm
, File file
) {
69 FileInputStream fis
= null;
70 FileChannel fc
= null;
72 fis
= new FileInputStream(file
);
73 fc
= fis
.getChannel();
75 // Get the file's size and then map it into memory
76 int sz
= (int) fc
.size();
77 ByteBuffer bb
= fc
.map(FileChannel
.MapMode
.READ_ONLY
, 0, sz
);
78 return digest(algorithm
, bb
);
79 } catch (IOException e
) {
80 throw new UtilsException("Cannot digest " + file
+ " with algorithm " + algorithm
, e
);
82 StreamUtils
.closeQuietly(fis
);
86 } catch (IOException e
) {
92 protected static String
digest(String algorithm
, ByteBuffer bb
) {
93 long begin
= System
.currentTimeMillis();
95 MessageDigest digest
= MessageDigest
.getInstance(algorithm
);
97 byte[] checksum
= digest
.digest();
98 String res
= encodeHexString(checksum
);
99 long end
= System
.currentTimeMillis();
101 System
.out
.println((end
- begin
) + " ms / " + ((end
- begin
) / 1000) + " s");
103 } catch (NoSuchAlgorithmException e
) {
104 throw new UtilsException("Cannot digest with algorithm " + algorithm
, e
);
108 public static void main(String
[] args
) {
111 file
= new File(args
[0]);
113 System
.err
.println("Usage: <file> [<algorithm>]" + " (see http://java.sun.com/j2se/1.5.0/"
114 + "docs/guide/security/CryptoSpec.html#AppA)");
118 if (args
.length
> 1) {
119 String algorithm
= args
[1];
120 System
.out
.println(digest(algorithm
, file
));
122 String algorithm
= "MD5";
123 System
.out
.println(algorithm
+ ": " + digest(algorithm
, file
));
125 System
.out
.println(algorithm
+ ": " + digest(algorithm
, file
));
126 algorithm
= "SHA-256";
127 System
.out
.println(algorithm
+ ": " + digest(algorithm
, file
));
128 algorithm
= "SHA-512";
129 System
.out
.println(algorithm
+ ": " + digest(algorithm
, file
));
133 final private static char[] hexArray
= "0123456789ABCDEF".toCharArray();
137 * http://stackoverflow.com/questions/9655181/how-to-convert-a-byte-array-to
138 * -a-hex-string-in-java
140 private static String
encodeHexString(byte[] bytes
) {
141 char[] hexChars
= new char[bytes
.length
* 2];
142 for (int j
= 0; j
< bytes
.length
; j
++) {
143 int v
= bytes
[j
] & 0xFF;
144 hexChars
[j
* 2] = hexArray
[v
>>> 4];
145 hexChars
[j
* 2 + 1] = hexArray
[v
& 0x0F];
147 return new String(hexChars
);