MD5加密算法

 1 // MD5加密，32位
 2     public static String MD5(String str) {
 3         MessageDigest md5 = null;
 4         try {
 5             md5 = MessageDigest.getInstance("MD5");
 6         } catch (Exception e) {
 7             e.printStackTrace();
 8             return "";
 9         }
10         char[] charArray = str.toCharArray();
11         byte[] byteArray = new byte[charArray.length];
12         for (int i = 0; i < charArray.length; i++) {
13             byteArray[i] = (byte) charArray[i];
14         }
15         byte[] md5Bytes = md5.digest(byteArray);
16         StringBuffer hexValue = new StringBuffer();
17         for (int i = 0; i < md5Bytes.length; i++) {
18             int val = ((int) md5Bytes[i]) & 0xff;
19             if (val < 16) {
20                 hexValue.append("0");
21             }
22             hexValue.append(Integer.toHexString(val));
23         }
24         return hexValue.toString();
25     }