MD5算法的应用

public class MD5Test {

 /**
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub

  MD5Test md5Test = new MD5Test();
  System.out.println(md5Test.MD5Encode("11123456"));
  System.out.println(md5Test.MD5Encode("11123456"));
  System.out.println(md5Test.MD5Encode("w11n123456"));
 }
 

  private final static String[] hexDigits = { "0", "1", "2", "3", "4", "5",
    "6", "7", "8", "9", "a", "b", "c", "d", "e", "f" };

  /**
   * 转换字节数组为16进制字串
   *
   * @param b
   *            字节数组
   * @return 16进制字串
   */

  public static String byteArrayToHexString(byte[] b) {
   StringBuffer resultSb = new StringBuffer();
   for (int i = 0; i < b.length; i++) {
    resultSb.append(byteToHexString(b[i]));
   }
   return resultSb.toString();
  }

  private static String byteToHexString(byte b) {
   int n = b;
   if (n < 0)
    n = 256 + n;
   int d1 = n / 16;
   int d2 = n % 16;
   return hexDigits[d1] + hexDigits[d2];
  }

  public static String MD5Encode(String origin) {
   String resultString = null;

   try {
    resultString = new String(origin);
    MessageDigest md = MessageDigest.getInstance("MD5");
    resultString = byteArrayToHexString(md.digest(resultString
      .getBytes()));
   } catch (Exception ex) {

   }
   return resultString;
  }

 }