簡單實現MD5加密字串
阿新 • • 發佈：2019-02-14
{
6
7
private final static String[] hexDigits = {
8 "0", "1", "2", "3", "4", "5", "6", "7",
9
"8", "9", "a", "b", "c", "d", "e", "f"};
10
11 /**12 * 轉換位元組陣列為16進位制字串
13 * @param b 位元組陣列
14 * @return 16進位制字串
15 */
16
17 public static String byteArrayToHexString(byte
18 StringBuffer resultSb = new StringBuffer();
19 for (int i = 0; i < b.length; i++) {
20 resultSb.append(byteToHexString(b[i]));
21 }
22 return resultSb.toString();
23 }
24
25 private static String byteToHexString(byte b) {
26 int n = b;
27
28 n = 256 + n;
29 int d1 = n / 16;
30 int d2 = n % 16;
31 return hexDigits[d1] + hexDigits[d2];
32 }
33
34 public static String MD5Encode(String origin) {
35 String resultString = null;
36
37 try {
38 resultString=new String(origin);
39
40 resultString=byteArrayToHexString(md.digest(resultString.getBytes()));
41 }
42 catch (Exception ex) {
43
44 }
45 return resultString;
46 }
47
48 public static void main(String[] args){
49 System.err.println(MD5Encode(""));
50 System.err.println(MD5Encode("a"));
51 System.err.println(MD5Encode("abc"));
52 System.err.println(MD5Encode("message digest"));
53 System.err.println(MD5Encode("abcdefghijklmnopqrstuvwxyz"));
54
55 }
56
57 //MD5 ("") = d41d8cd98f00b204e9800998ecf8427e
58 //MD5 ("a") = 0cc175b9c0f1b6a831c399e269772661
59 //MD5 ("abc") = 900150983cd24fb0d6963f7d28e17f72
60 //MD5 ("message digest") = f96b697d7cb7938d525a2f31aaf161d0
61 //MD5 ("abcdefghijklmnopqrstuvwxyz") = c3fcd3d76192e4007dfb496cca67e13b62
63
64
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}
6
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private final static String[] hexDigits = { 8
"0", "1", "2", "3", "4", "5", "6", "7", 9
"8", "9", "a", "b", "c", "d", "e", "f"}; 10
11
/**12 * 轉換位元組陣列為16進位制字串 13
* @param b 位元組陣列 14
* @return 16進位制字串 15
*/ 16
17
public static String byteArrayToHexString(byte18
StringBuffer resultSb = new StringBuffer(); 19
for (int i = 0; i < b.length; i++) { 20
resultSb.append(byteToHexString(b[i])); 21
} 22
return resultSb.toString(); 23
} 24
25
private static String byteToHexString(byte b) { 26
int n = b; 27
if (n < 0) 28
n = 256 + n; 29
int d1 = n / 16; 30
int d2 = n % 16; 31
return hexDigits[d1] + hexDigits[d2]; 32
} 33
34
public static String MD5Encode(String origin) { 35
String resultString = null; 36
37
try { 38
resultString=new String(origin); 39
MessageDigest md = MessageDigest.getInstance("MD5"); 40
resultString=byteArrayToHexString(md.digest(resultString.getBytes())); 41
} 42
catch (Exception ex) { 43
44
} 45
return resultString; 46
} 47
48
public static void main(String[] args){ 49
System.err.println(MD5Encode("")); 50
System.err.println(MD5Encode("a")); 51
System.err.println(MD5Encode("abc")); 52
System.err.println(MD5Encode("message digest")); 53
System.err.println(MD5Encode("abcdefghijklmnopqrstuvwxyz")); 54
55
} 56
57
//MD5 ("") = d41d8cd98f00b204e9800998ecf8427e58
//MD5 ("a") = 0cc175b9c0f1b6a831c399e26977266159
//MD5 ("abc") = 900150983cd24fb0d6963f7d28e17f7260
//MD5 ("message digest") = f96b697d7cb7938d525a2f31aaf161d061
//MD5 ("abcdefghijklmnopqrstuvwxyz") = c3fcd3d76192e4007dfb496cca67e13b62 63
64
65
}