SpringBoot向Excel模板中写入数据并下载 （无需获取file对象及模板绝对路径）

之前用获取模板路径的方式测试没问题打包后就有问题了

莫名出现一个！ 找了很多教程尝试无果 最终使用下面这个方式
无需获取file对象以及模板路径的方式进行写入下载
（那个设置浏览器编码没有测试不知道能不能用！！！）

 public void export(SampleFilterAO filter, HttpServletResponse response, HttpServletRequest request) {          Map<String, Object> map = new HashMap<>();         // 获取导出的时间参数         String date = request.getParameter("Date");         map.put("Date", date);         String fileName = "data.xlsx";         // 使用类加载器获取excel文件流,基于模板填充数据         ClassPathResource classPathResource = new ClassPathResource(fileName);         InputStream is = null;         XSSFWorkbook workbook = null;         try {             is = classPathResource.getInputStream();             workbook = new XSSFWorkbook(is);             XSSFSheet sheet = null;             // 获取第一个sheet页             // getSheet的参数是sheet的名称， 获取具体名称的sheet。             sheet = workbook.getSheetAt(0);             Long offset = (filter.getPage() - 1) * filter.getLimit();             filter.setOffset(offset);             filter.setLimit(sampleMapper.count(filter).intValue());             List<Sample> resutList = sampleMapper.list(filter);             for (int i = 0; i < resutList.size(); i++) {                 Integer j=i+1;                 writeExcel(sheet, resutList, j, i);             }         } catch (IOException e) {             e.printStackTrace();         }         //文件下載         response.reset();         response.setContentType("text/html;charset=UTF-8");         response.setContentType("application/x-msdownload");         String newName = "";         try {             newName = URLEncoder.encode("扫描记录导出" + System.currentTimeMillis() + ".xlsx", "UTF-8");             String s = encodeFileName(request,newName);             response.addHeader("Content-Disposition", "attachment;filename="" + s + """);             OutputStream toClient = new BufferedOutputStream(response.getOutputStream());             workbook.write(toClient);             toClient.flush();         } catch (UnsupportedEncodingException e) {             // TODO Auto-generated catch block             e.printStackTrace();         } catch (IOException e) {             // TODO Auto-generated catch block             e.printStackTrace();         }      } 	//写入数据的方法     public void writeExcel(XSSFSheet sheet, List<Sample> resutList,Integer rownum, Integer index) {         if (resutList.get(index) != null && !"".equals(resutList.get(index))) {             Row row = sheet.createRow(rownum);              Cell cell = row.createCell(0); //序号             cell.setCellValue(index+1);              String sampleNo = resutList.get(index).getSampleNo();// 玻片编号             cell = row.createCell(1);             cell.setCellValue(sampleNo);              String patientNo = resutList.get(index).getPatientNo();// 病案号             cell = row.createCell(2);             cell.setCellValue(patientNo);              String patientName = resutList.get(index).getPatientName();// 姓名             cell = row.createCell(3);             cell.setCellValue(patientName);              String patientSex = resutList.get(index).getPatientSex();// 性别             cell = row.createCell(4);             cell.setCellValue(patientSex);              String position = resutList.get(index).getPosition();// 部位             cell = row.createCell(5);             cell.setCellValue(position);              String aiResultId = resutList.get(index).getAiResultId();// AI检验结果             cell = row.createCell(6);             cell.setCellValue(aiResultId);              String createdName = resutList.get(index).getCreatedName();// 扫描人员             cell = row.createCell(7);             cell.setCellValue(createdName);              Long createdAt = resutList.get(index).getCreatedAt();// 记录时间             SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");             String time = format.format(createdAt);             cell = row.createCell(8);             cell.setCellValue(time);         }     } 	//不同浏览器设置不同编码（未测试！）     public static String encodeFileName(HttpServletRequest request, String fileName)             throws UnsupportedEncodingException {          String newFilename = URLEncoder.encode(fileName, "UTF8").replaceAll("\+", "%20");          String agent = request.getHeader("USER-AGENT").toLowerCase();         if (null != agent && -1 != agent.indexOf("msie")) {             /**              * IE浏览器，只能采用URLEncoder编码              */             return newFilename;         } else if (null != agent && -1 != agent.indexOf("applewebkit")) {             /**              * Chrome浏览器，只能采用ISO编码的中文输出              */             return new String(fileName.getBytes("UTF-8"), "ISO8859-1");         } else if (null != agent && -1 != agent.indexOf("opera")) {             /**              * Opera浏览器只可以使用filename*的中文输出              * RFC2231规定的标准              */             return newFilename;         } else if (null != agent && -1 != agent.indexOf("safari")) {             /**              * Safani浏览器，只能采用iso编码的中文输出              */             return new String(fileName.getBytes("UTF-8"), "ISO8859-1");         } else if (null != agent && -1 != agent.indexOf("firefox")) {             /**              * Firfox浏览器，可以使用filename*的中文输出              * RFC2231规定的标准              */             return newFilename;         } else {             return newFilename;         }     } 

本文转自：https://blog.csdn.net/wongrock/article/details/118359816