MD5加密

public static String getMD5(String str) {
    try {
        byte[] res = str.getBytes();
        MessageDigest md = MessageDigest.getInstance("MD5".toUpperCase());
        byte[] result = md.digest(res);
        for (int i = 0; i < result.length; i++) {
            md.update(result[i]);
    }
        byte[] hash = md.digest();
        StringBuffer d = new StringBuffer("");
        for (int i = 0; i < hash.length; i++) {
            int v = hash[i] & 0xFF;
            if (v < 16)
                d.append("0");
            d.append(Integer.toString(v, 16).toUpperCase() + "");
        }
        return d.toString();
    } catch (Exception e) {
        // LOG.error("Encrypt MD5 failed.", e);
        return "";
    }
}