xml to string

String modelXML = convertXMLFileToString("/Temp/source_backup/" +prdModels[i].trim()+ ".xml");

    /** XML to String **/
    public String convertXMLFileToString(String fileName)
    {
        try
        {
            DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance();
            InputStream inputStream = new FileInputStream(new File(fileName));
            org.w3c.dom.Document doc = documentBuilderFactory.newDocumentBuilder().parse(inputStream);
            StringWriter stw = new StringWriter();
            Transformer serializer = TransformerFactory.newInstance().newTransformer();
            serializer.transform(new DOMSource(doc), new StreamResult(stw));
            return stw.toString();
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
        return "";
    }