İşte kod kullanılmakta.

public String getStringFromDoc(org.w3c.dom.Document doc)    {
        try
        {
           DOMSource domSource = new DOMSource(doc);
           StringWriter writer = new StringWriter();
           StreamResult result = new StreamResult(writer);
           TransformerFactory tf = TransformerFactory.newInstance();
           Transformer transformer = tf.newTransformer();
           transformer.transform(domSource, result);
           writer.flush();
           return writer.toString();
        }
        catch(TransformerException ex)
        {
           ex.printStackTrace();
           return null;
        }
    }

Güvenir DOM Level3 Load/Save:

public String getStringFromDoc(org.w3c.dom.Document doc)    {
    DOMImplementationLS domImplementation = (DOMImplementationLS) doc.getImplementation();
    LSSerializer lsSerializer = domImplementation.createLSSerializer();
    return lsSerializer.writeToString(doc);   
}