private static final String EXCEL_XLS = "xls";private static final String EXCEL_XLSX = "xlsx";/*** 判断Excel的版本,获取Workbook* @param in* @param file* @return* @throws IOException*/public static Workbook getWorkbok(InputStream in, MultipartFile file) throws IOException {Workbook wb = null;if(file.getOriginalFilename().endsWith(EXCEL_XLS)){     //Excel 2003wb = new HSSFWorkbook(in);}else if(file.getOriginalFilename().endsWith(EXCEL_XLSX)){    // Excel 2007/2010wb = new XSSFWorkbook(in);}return wb;}/*** 判断文件是否是excel* @throws Exception*/public static void checkExcelVaild(MultipartFile file) throws Exception{if(ToolUtil.isEmpty(file)){throw new Exception("文件不存在");}if(!((file.getOriginalFilename().endsWith(EXCEL_XLS) || file.getOriginalFilename().endsWith(EXCEL_XLSX)))){throw new Exception("文件不是Excel");}}/*** 读取Excel，兼容 Excel 2003/2007/2010     * @param excelFile　　　* @param sheetIndex　　从第几个sheet开始遍历     * @param dataRowIndex　　从第几行开始遍历     * @throws Exception*/public static List<Map<String, Object>> parseExcelObject(MultipartFile excelFile, int sheetIndex, int dataRowIndex) {List<Map<String,Object>> lists = new ArrayList<>();SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd");try {// 同时支持Excel 2003、2007FileInputStream is = (FileInputStream) excelFile.getInputStream(); // 文件流
            checkExcelVaild(excelFile);Workbook workbook = getWorkbok(is,excelFile);//Workbook workbook = WorkbookFactory.create(is); // 这种方式 Excel2003/2007/2010都是可以处理的/*** 设置当前excel中sheet的下标：sheetIndex*/if(sheetIndex >= 0 && sheetIndex < workbook.getNumberOfSheets()){for (; sheetIndex < workbook.getNumberOfSheets(); sheetIndex++){int rowSize = 0;Sheet sheet = workbook.getSheetAt(sheetIndex);for(int rowIndex = dataRowIndex; rowIndex <= sheet.getLastRowNum(); rowIndex++){Row row = sheet.getRow(rowIndex);if(row == null)continue;int tempRowSize = row.getLastCellNum();if(tempRowSize > rowSize)rowSize = tempRowSize;Map<String, Object> maps = new HashMap<String, Object>();String rowValue = "";for(short columnIndex = 0; columnIndex < row.getLastCellNum(); columnIndex++){Cell cell = row.getCell(columnIndex);if(ToolUtil.isEmpty(cell))continue;int cellType = cell.getCellType();String cellValue = "";switch (cellType){case Cell.CELL_TYPE_STRING:        // 文本cellValue = cell.getRichStringCellValue().getString().trim();break;case Cell.CELL_TYPE_NUMERIC:    // 数字、日期if (DateUtil.isCellDateFormatted(cell)) {cellValue = fmt.format(cell.getDateCellValue());} else {cell.setCellType(Cell.CELL_TYPE_STRING);cellValue = String.valueOf(cell.getRichStringCellValue().getString());}break;case Cell.CELL_TYPE_BOOLEAN:    // 布尔型cellValue = String.valueOf(cell.getBooleanCellValue());break;case Cell.CELL_TYPE_BLANK: // 空白cellValue = cell.getStringCellValue();break;case Cell.CELL_TYPE_ERROR: // 错误cellValue = "";break;case Cell.CELL_TYPE_FORMULA:    // 公式// 得到对应单元格的公式//cellValue = cell.getCellFormula() + "#";// 得到对应单元格的字符串
                                    cell.setCellType(Cell.CELL_TYPE_STRING);cellValue = String.valueOf(cell.getRichStringCellValue().getString());break;default:cellValue = "";}//  保存数据if (columnIndex == 0){maps.put("name", cellValue);} 　　　　　　　　　　　　　　　　 // ......其他逻辑......
                        }lists.add(maps);}}}is.close();   //关闭文件流
} catch (Exception e) {e.printStackTrace();} finally{}return lists;}

/*** 导入excel** @param multipartFile* @return*/
@RequestMapping(value = "/importExcel", method = RequestMethod.POST)
@ResponseBody
public void importExcel(@RequestParam("file") MultipartFile multipartFile) {if (multipartFile == null) {throw new Exception("excel文件请求参数错误");}List<Map<String, Object>> list = ExcelUtil.parseExcelObject(multipartFile, 0, 0); // 这里只解析第一个sheet，从第一行开始for(Map<String, Object> map : list){System.out.println(map.getString("name"));}
}

public static XSSFWorkbook createExcelObject(List<ExcelObject> list) {SimpleDateFormat fmt = new SimpleDateFormat("yyyy-MM-dd");try {// 第一步,创建一个webbook文件,对应一个excel文件XSSFWorkbook wb = new XSSFWorkbook();// 第二部,在excel中添加一个sheet工作簿,参数为该工作簿名字,不写为默认;XSSFSheet sheet = wb.createSheet("sheet1");// 第三部,做sheet中添加表头第0行,注意老版本poi对excel的行数列数有限制shortXSSFRow row = sheet.createRow((int) 0);// 第四部,设置单元格样式XSSFCellStyle style = wb.createCellStyle();style.setAlignment(HorizontalAlignment.CENTER);//创建一个居中格式// 生成字体Font font = wb.createFont();font.setFontHeightInPoints((short) 12);font.setBold(true);// 把字体应用到当前的样式
            style.setFont(font);// 第五部,设置好表头内容XSSFCell cell = row.createCell(0);cell.setCelSPUue("name");cell.setCellStyle(style)// 第六部,写入实体数据 实际应用中这些数据应该是从数据库中得到for (int i = 0; i < list.size(); i++) {// 每次新建一行然后在新行中插入list中的数据对象,有点繁琐,也许有更好的封装方法,留待后看row = sheet.createRow((int) i + 1);row.createCell((int) 0).setCellValue(list.get(i).getName());}return wb;} catch (Exception e) {e.printStackTrace();} finally {}return null;}    

/*** 导出商品信息** @param request* @param response* @throws Exception*/
@RequestMapping(value = "/downExcel",method = RequestMethod.POST)
@ResponseBody
public void downExcel(HttpServletRequest request, HttpServletResponse response){List<ExcelObject> list; // 查询出来的数据// 正确代码顺序//FileInputStream fs=new FileInputStream(excel);//XSSFWorkbook workbook = new XSSFWorkbook(fs);//FileOutputStream out=new FileOutputStream(excel);//workbook.write(out);
XSSFWorkbook wb = ExcelUtil.createExcelObject(list);if (wb == null)throw new Exception("excel文件解析异常");try {// 设置输出的格式response.reset();// 清空输出流response.setHeader("Content-Disposition", "attachment; filename=" + new String(("excel.xlsx").getBytes(), "iso-8859-1"));// 设定输出文件头response.setContentType("application/x-download;charset=GBK");// 定义输出类型//创建输出流OutputStream outputStream = response.getOutputStream();wb.write(outputStream);outputStream.close();}catch (Exception e){e.printStackTrace();}
}