log.info(document.getDocumentElement());
if (log.isDebugEnabled()) log.debug(document.getDocumentElement());
    private void parse() {    	try {    		Document document = null;    		DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();    		dbf.setNamespaceAware(true);    		dbf.setIgnoringElementContentWhitespace(true);    		DocumentBuilder builder = dbf.newDocumentBuilder();    		InputStream stream = _contentStream;    		document = builder.parse(stream);    		    		_workbook = new HSSFWorkbook();    		    		log.info(document.getDocumentElement());    		    		NodeList nodes = document.getDocumentElement().getChildNodes();    		for (int i = 0; i < nodes.getLength(); i++) {    			Node node = nodes.item(i);    			if(node.getNodeType() == Node.ELEMENT_NODE) {    				parseNode(node);    			}    		}    	} catch(Exception ex) {    		throw new NSForwardException(ex);    	}    }