Excel导出

 <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>4.1.0</version>
 </dependency>

   @GetMapping("/export")
    public ResponseEntity<byte[]> exportExcel() throws IOException {
        return POIUtils.exportExcel((List<Position>) positionService.getAllPosition(null,null).getData());

    }

   public RespPageBean getAllPosition(Integer page,Integer size) {
        if (page!=null&&size!=null) {
            page = (page - 1) * size;
        }
      List<Position> list= positionMapper.getAllPosition(page,size);
      RespPageBean respPageBean=new RespPageBean();
      respPageBean.setData(list);
      respPageBean.setTotal(positionMapper.getTotal());
        return respPageBean;
    }

 <select id="getAllPosition" resultMap="BaseResultMap">
    select * from position
    <if test="page !=null and size !=null">
      limit #{page},#{size}
    </if>
  </select>

public class POIUtils {
    public static ResponseEntity<byte[]> exportExcel(List<Position> positions) throws IOException {
        HSSFWorkbook workbook = new HSSFWorkbook();
        workbook.createInformationProperties();
        SummaryInformation information = workbook.getSummaryInformation();
        information.setTitle("职位表");
        information.setAuthor("javaboy");
        information.setComments("备注");

        HSSFSheet hssfSheet = workbook.createSheet("职位表");//创建表格对象，并定义表名称
        HSSFRow row0 = hssfSheet.createRow(0);//创建字段行
        HSSFCell c0 = row0.createCell(0);//创建第一列
        HSSFCell c1 = row0.createCell(1);
        HSSFCell c2 = row0.createCell(2);
        HSSFCell c3 = row0.createCell(3);
        c0.setCellValue("编号");//设置第一行第一列字段
        c1.setCellValue("名称");
        c2.setCellValue("创建时间");
        c3.setCellValue("是否启用");
  
        HSSFCellStyle dateCellStyle = workbook.createCellStyle();
        dateCellStyle.setDataFormat(HSSFDataFormat.getBuiltinFormat("m/d/yy"));//设置日期格式
        for (int i = 0; i < positions.size(); i++) {
            HSSFRow r = hssfSheet.createRow(i + 1);
            HSSFCell cell0 = r.createCell(0);
            Position p = positions.get(i);
            ((HSSFCell) cell0).setCellValue(p.getId());//设置对应数据
            HSSFCell cell1 = r.createCell(1);
            ((HSSFCell) cell1).setCellValue(p.getName());
            HSSFCell cell2 = r.createCell(2);
            cell2.setCellStyle(dateCellStyle);
            ((HSSFCell) cell2).setCellValue(p.getCreatedate());
            HSSFCell cell3 = r.createCell(3);
            ((HSSFCell) cell3).setCellValue(p.getEnabled() ? "是" : "否");
        }

        HttpHeaders headers = new HttpHeaders();
        headers.setContentDispositionFormData("attachment",
                new String("职位表222.xls".getBytes("UTF-8"), "iso-8859-1"));
        headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);
        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        workbook.write(baos);
        return new ResponseEntity<>(baos.toByteArray(), headers, HttpStatus.CREATED);
    }
}