• 准备工作把自己需要需要导出的表格  
• 第一行为一个一对多的数据结构 在需要填入值的框里 {属性名}
• 第三行以后对应的为一个数组  {.属性名}

准备工作做好以后把表格（.xlxs）放入静态资源文件夹里面  

代码如下

 @Override
    public ResultDTO downloadOfferList(OfferDownlod bc31) throws Exception {
        List<OfferDownlod> dataset = null;
        //一对一的数据
        Map<String, Object> map = new HashMap<>();
        map.put("Businesstype", "C3-人民币跨行代付(多对多)");
        map.put("Outaccount",bc31.getBab084());//转出账号
        map.put("Bizhon", "CNY-人民币");
        map.put("BusinessSummary", "EV-工资");
        String fileName="";
        //数组的数据来源
        dataset = bc31Mapper.queryBpBc31List(bc31);
        //刚刚准备好的表格文件
        fileName="/file/hangwai.xlsx";
       
        if(!StringUtils.isEmpty(dataset)){
            ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
            InputStream inputStream = this.getClass().getResourceAsStream(fileName);
            ServletRequestAttributes sra = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
            HttpServletResponse response = sra.getResponse();
            response.setContentType("multipart/form-data;charset=UTF-8");
            response.setHeader("Accept-Language", "zh-cn");
            response.setHeader("Content-Disposition", "attachment; filename=" + URLEncoder.encode("基础信息.xlsx", "UTF-8"));

            OutputStream os = response.getOutputStream();
            FillConfig fillConfig = FillConfig.builder().forceNewRow(Boolean.TRUE).build();
            ExcelWriter excelWriter = EasyExcel.write(os).withTemplate(inputStream).build();
            //创建第一个sheet
            WriteSheet bc09Sheet = EasyExcel.writerSheet("Sheet1").build();
            //填充
            excelWriter.fill(dataset, fillConfig, bc09Sheet);
            excelWriter.fill(map, bc09Sheet);
            excelWriter.finish();
     
            return new ResultDTO(0, "查询成功");
        }else{
            return new ResultDTO(0,"查询成功,暂无数据");
        }

    }

 下载文件得