背景

有个功能需要导入导出多sheet页的Excel，以前用poi搞，想试下用hutool处理一下。接口已弄完，简单总结一下。

导入

controller

正常使用就行，header的参数用来确认租户

@ApiOperation(value = "导入字段分组excel", notes = "")@PostMapping(value = "/import/field")public R importFieldGroupModel(MultipartFile file, String ruleId, String mapId, @RequestHeader(BasePlatformConstant.TENANT_ID) String tenantId) {return pmFieldGroupService.importExcel(file, ruleId, mapId,tenantId);}

service

我是通过制定sheet页的顺序，来读取sheet内容
ExcelReader sheetReader = ExcelUtil.getReader(file.getInputStream(), i);
官方给出的文档：
https://doc.hutool.cn/pages/ExcelReader/
https://doc.hutool.cn/pages/ExcelUtil

/*** 导入字段分组Excel模板* @param file     字段分组Excel* @param ruleId   规则id* @param mapId    地图id* @param tenantId 租户id*/@Overridepublic R importExcel(MultipartFile file, String ruleId, String mapId, String tenantId) {String aliasNameException = "";String sheetNameException = "";try {InputStream inputStream = file.getInputStream();ExcelReader readerAll = ExcelUtil.getReader(inputStream);int sheetCount = readerAll.getSheetCount();List<String> sheetNameList = readerAll.getSheetNames();for (int i = 0; i < sheetCount; i++) {// 获取图层名称String sheetName = sheetNameList.get(i);sheetNameException = sheetName;        ExcelReader sheetReader = ExcelUtil.getReader(file.getInputStream(), i);  List<Map<String, Object>> sheetFieldGroup = sheetReader.readAll();    List<PmFieldGroupVO> targetPpmFieldGroupVOList = new ArrayList<>();for (Map fieldInfo : sheetFieldGroup) {// 遍历sheet页中记录，构造需要导入的对象PmFieldGroupVO pmFieldGroupVO = new PmFieldGroupVO();pmFieldGroupVO.setRuleId(ruleId);pmFieldGroupVO.setLayerId(layerId);pmFieldGroupVO.setFieldName(fieldname);pmFieldGroupVO.setGroupId(baseGroup.getId());pmFieldGroupVO.setOrders(order == null ? 10 : order);targetPpmFieldGroupVOList.add(pmFieldGroupVO);}save(targetPpmFieldGroupVOList);}} catch (Exception exception) {exception.printStackTrace();log.error(exception.getMessage());log.error("异常图层名称" + sheetNameException);log.error("异常字段名称：" + aliasNameException);return R.error(exception.getMessage());}return R.ok();}

导出

controller

   @ApiOperation(value = "导出字段分组excel", notes = "")@PostMapping(value = "/export/field")public void exportFieldGroupModel(@RequestBody PmLayerVO vo, HttpServletResponse response) {pmFieldGroupService.exportExcel(vo,response);}

service

ExcelWriter对象默认使用的是第一个sheet页。因此需要根据实际情况决定是否需要重命名
writer.renameSheet(layersEntityList.get(0).getName());//重命名sheet页
切换sheet页也是创建sheet页。可以直接指定sheet页名称
writer.setSheet(layersEntityList.get(i).getName());

注

需要注意的是，切换sheet页后需要设置样式。

 public void exportExcel(PmLayerVO vo, HttpServletResponse response) {try {ExcelWriter writer = ExcelUtil.getWriter(true);//单元格宽度高度writer.setColumnWidth(-1, 18);writer.setRowHeight(-1, 20);writer.setOnlyAlias(true);// 定义单元格背景色StyleSet style = writer.getStyleSet();// 第二个参数表示是否也设置头部单元格背景style.setBackgroundColor(IndexedColors.WHITE, true);Map<String, String> apiModelProperty = ClassPropertyCommentsUtils.getApiModelProperty(new FieldGroupVO());// 第一个图层/sheet页需要特殊处理List<FieldGroupVO> firstLayerFieldGroupList = getFieldGroupByLayerIdRuleId(vo.getRuleId(),layersEntityList.get(0).getId());writer.renameSheet(layersEntityList.get(0).getName());if (firstLayerFieldGroupList.size() > 0) {apiModelProperty.forEach((k, v) -> writer.addHeaderAlias(v, k));writer.write(firstLayerFieldGroupList, true);}// 按图层构建分组信息for (int i = 1; i < layersEntityList.size(); i++) {// 切换sheet页writer.setSheet(layersEntityList.get(i).getName());List<FieldGroupVO> layerFieldGroupList = getFieldGroupByLayerIdRuleId(vo.getRuleId(),layersEntityList.get(i).getId());apiModelProperty.forEach((k, v) -> writer.addHeaderAlias(v, k));//单元格宽度高度writer.setColumnWidth(-1, 18);writer.setRowHeight(-1, 20);writer.setOnlyAlias(true);writer.write(layerFieldGroupList, true);}ExportFileUtil.setResponseHeader(response, "信息表" + DateTime.now().getTime() + ".xlsx");OutputStream os = response.getOutputStream();writer.flush(os);os.flush();os.close();} catch (Exception e) {e.printStackTrace();}}

工具类

获取对象的ApiModelProperty注释

/*** 获取类注释**/
public class ClassPropertyCommentsUtils {public static Map<String, String> getApiModelProperty(Object obj) {try {// 1.根据类路径获取类Class<?> c = obj.getClass();// 2.获取类的属性Field[] declaredFields = c.getDeclaredFields();Map<String, String> map = new LinkedHashMap<>(declaredFields.length);// 3.遍历属性，获取属性上ApiModelProperty的值，属性的名，存入Propertiesif (declaredFields.length != 0) {for (Field field : declaredFields) {if (field.getAnnotation(ApiModelProperty.class) != null) {map.put(field.getAnnotation(ApiModelProperty.class).value(), field.getName());}}return map;}} catch (Exception e) {}return null;}public static void nullifyStrings(Object o) {for (Field f : o.getClass().getDeclaredFields()) {f.setAccessible(true);try {if (f.getType().equals(String.class)) {String value = (String) f.get(o);if (value != null && value.trim().isEmpty()) {f.set(o, null);}}} catch (Exception e) {throw new RuntimeException(e);}}}
}

导出Excel工具类中设置响应头的函数

/*设置浏览器下载响应头*/public static void setResponseHeader(HttpServletResponse response, String fileName) {try {try {fileName = new String(fileName.getBytes(), "ISO8859-1");} catch (UnsupportedEncodingException e) {e.printStackTrace();}response.setContentType("application/vnd.ms-excel;charset=UTF-8");response.setHeader("Content-Disposition", "attachment;filename=" + fileName);response.addHeader("Pargam", "no-cache");response.addHeader("Cache-Control", "no-cache");} catch (Exception ex) {ex.printStackTrace();}}