/**	 * 返回上传的Excel表格的内容	 */	public static List<String[]> parseExcel(InputStream is) throws Exception {		List<String[]> list = new ArrayList<>();		Workbook wb = Workbook.getWorkbook(is);		Sheet sheet = wb.getSheets()[0];		int columns = sheet.getRow(0).length;		for (int i = 0; i < sheet.getRows(); i++) {			String[] line = new String[columns];			for (int j = 0; j < columns; j++) {				Cell cell = sheet.getCell(j, i);				String content = null;				if (cell != null) {					content = cell.getContents();				}				if (content != null && content.trim().length() == 0) {					content = null;				}				line[j] = content;			}			list.add(line);		}		return list;	}