MD5加密

 public class MD5 {
 public MD5() {
 }

 public static String encode(String source) {
  try {
   char hexs[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9','a', 'b', 'c', 'd', 'e', 'f' };
   char result[];
   MessageDigest digester = MessageDigest.getInstance("MD5");
   byte sbs[] = source.getBytes("UTF8");
   digester.update(sbs);
   byte rbs[] = digester.digest();
   int j = rbs.length;
   result = new char[j * 2];
   int k = 0;
   for (int i = 0; i < j; i++) {
    byte b = rbs[i];
    result[k++] = hexs[b >>> 4 & 0xf];
    result[k++] = hexs[b & 0xf];
   }

   return new String(result);
  } catch (Exception e) {
   e.printStackTrace();
   return null;
  }
 }
}