Bug 361443 Excel ODA
data/org.eclipse.birt.report.data.oda.excel/src/org/eclipse/birt/report/data/oda/excel/impl/util/XlsxFileReader.java
public void startElement(String uri, String localName, String qName,
				Attributes attributes) throws SAXException {
			if (qName.equals("c")) {
				String vCellType = attributes.getValue("t");
				String cellS = attributes.getValue("s");
				if ("b".equals(vCellType))
					cellDataType = cDataType.BOOL;
				else if ("e".equals(vCellType))
					cellDataType = cDataType.FORMULA;
				else if ("s".equals(vCellType))
					cellDataType = cDataType.SSTINDEX;
				else if("str".equals(vCellType))
					cellDataType =  cDataType.STATIC;
		        else if (cellS != null) {
		              
		            int styleIndex = Integer.parseInt(cellS);
		            XSSFCellStyle style = st.getStyleAt(styleIndex);
		            short formatIndex = style.getDataFormat();
		            String formatString = style.getDataFormatString();
		            if (formatString == null)
		                   formatString = BuiltinFormats.getBuiltinFormat(formatIndex);
		            if( org.apache.poi.ss.usermodel.DateUtil.isADateFormat(formatIndex, formatString) ){
				cellDataType =  cDataType.DATETIME;
		            }else{
				cellDataType = cDataType.NUMBER;
		            }
		        }
				else
					cellDataType = cDataType.NUMBER;
                String r = attributes.getValue("r");