public Node getUserNode(String uid) {
        NodeList userList = doc.getElementsByTagName("user");
        System.out.println(userList.getLength());

        for (int i = 0; i < userList.getLength(); i++) {
            Node node = userList.item(i);
            Element eElement = (Element) node;
            System.out.println(eElement.getAttribute("id") + eElement.getAttribute("balance"));
            if (eElement.getAttribute("id").equals(uid)) {
                return node;
            }
        }

        return null;
    }