JAVA通过md5方法进行加密

 1 import java.security.MessageDigest;
 2 import java.security.NoSuchAlgorithmException;
 3 /*
 4 * MD5 算法
 5 * 
 6 */
 7 public class MD5 {
 8 
 9 // 全局数组
10 private final static String[] strDigits = { "0", "1", "2", "3", "4", "5",
11 "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };
12 
13 public MD5() {
14 }
15 
16 // 返回形式为数字跟字符串
17 private static String byteToArrayString(byte bByte) {
18 int iRet = bByte;
19 // System.out.println("iRet="+iRet);
20 if (iRet < 0) {
21 iRet += 256;
22 }
23 int iD1 = iRet / 16;
24 int iD2 = iRet % 16;
25 return strDigits[iD1] + strDigits[iD2];
26 }
27 
28 // 返回形式只为数字
29 private static String byteToNum(byte bByte) {
30 int iRet = bByte;
31 System.out.println("iRet1=" + iRet);
32 if (iRet < 0) {
33 iRet += 256;
34 }
35 return String.valueOf(iRet);
36 }
37 
38 // 转换字节数组为16进制字串
39 private static String byteToString(byte[] bByte) {
40 StringBuffer sBuffer = new StringBuffer();
41 for (int i = 0; i < bByte.length; i++) {
42 sBuffer.append(byteToArrayString(bByte[i]));
43 }
44 return sBuffer.toString();
45 }
46 
47 public static String GetMD5Code(String strObj) {
48 String resultString = null;
49 try {
50 resultString = new String(strObj);
51 MessageDigest md = MessageDigest.getInstance("MD5");
52 // md.digest() 该函数返回值为存放哈希值结果的byte数组
53 resultString = byteToString(md.digest(strObj.getBytes()));
54 } catch (NoSuchAlgorithmException ex) { 
55 ex.printStackTrace();
56 }
57 return resultString;
58 }
59 }