public String getServerValue(String serverId, String nodeName) {
        NodeList serversNodes = document.getElementsByTagName("servers");
        NodeList serverNodes = serversNodes.item(0).getChildNodes();

        String value = null;
        for (int i = 0; i < serverNodes.getLength(); i++) {
            Node serverNode = serverNodes.item(i);
            if (serverNodes.item(i).hasChildNodes() && hasIdNodeName(serverNode, serverId)) {
                value = getValueFromNodeList(serverNode, nodeName);
            }
        }
        return value;
    }