public static String md5Hex (String message) {
        try {
            MessageDigest md =
                    MessageDigest.getInstance("MD5");
            return hex (md.digest(message.getBytes("CP1252")));
        } catch (NoSuchAlgorithmException e) {
        } catch (UnsupportedEncodingException e) {
        }
        return null;
    }
@Test
    public void testMd5Hex() {
        String md5 = HashUtil.md5Hex("stevehu@gmail.com");
        Assert.assertEquals(md5, "417bed6d9644f12d8bc709059c225c27");
    }