SpringBoot EasyPoi动态导入导出的两种方式实现方法详解

/**
 * @description  动态显示Excel导出列
 * @date 2022/8/31
 */
public class EasyPoiUtil<T> {
    /**
     * 需要被反射的对象，使用泛型规范传入对象
     */
    public T t;
    public void hiddColumn(String columnName, Boolean target) throws Exception {
        if (t == null) {
            throw new ClassNotFoundException("TARGET OBJECT NOT FOUNT");
        }
        if (StringUtils.isEmpty(columnName)) {
            throw new NullPointerException("COLUMN NAME NOT NULL");
        }
        if (target == null) {
            target = true;
        }
        // 获取目标对象的属性值
        Field field = t.getClass().getDeclaredField(columnName);
        // 获取注解反射对象
        Excel excelAnnon = field.getAnnotation(Excel.class);
        // 获取代理
        InvocationHandler invocationHandler = Proxy.getInvocationHandler(excelAnnon);
        Field excelField = invocationHandler.getClass().getDeclaredField("memberValues");
        // 因为这个字段是 private final 修饰，所以要打开权限
        excelField.setAccessible(true);
        Map memberValues = (Map) excelField.get(invocationHandler);
        memberValues.put("isColumnHidden", target);
    }
}

public List<ExportVo> batchLiveUserExport(LiveUser liveUser) {
        List<ExportVo> voList = baseMapper.batchLiveUserExport(liveUser);
        LiveInfo liveInfo = liveInfoService.getById(liveUser.getLiveId());
        if (liveInfo != null) {
            LiveSpecial liveSpecial = liveSpecialService.getById(liveInfo.getSpecialId());
            if ("2".equals(liveSpecial.getLivePlatform())) {
                setHiddColumn(voList,true);
            } else {
                setHiddColumn(voList,false);
            }
        }
        return voList;
    }
    private void setHiddColumn(List<ExportVo> list, Boolean value) {
        if (CollectionUtil.isNotEmpty(list)) {
            for (ExportVo vo : list) {
                EasyPoiUtil<ExportVo> easyPoiUtil = new EasyPoiUtil<>();
                easyPoiUtil.t = vo;
                // 是否导出 参与状态 一列  true 导出   false 不导出
                try {
                    easyPoiUtil.hiddColumn("isJoin", value);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        }
    }

   /**
     * 根据条件动态生成列信息
     **/
    private List<ExcelExportEntity> dynaCol(String type) {
        List<ExcelExportEntity> colList = new ArrayList<ExcelExportEntity>();
        colList.add(new ExcelExportEntity("姓名", "realName"));
        colList.add(new ExcelExportEntity("学号", "studNo"));
        if ("2".equals(type)) {
            colList.add(new ExcelExportEntity("手机号", "phoneNumber"));
            ExcelExportEntity excelentity = new ExcelExportEntity("通知状态", "isSms");
            // 值替换
            String[] isSmsReplace = {"未发送_N", "已发送_Y","_null"};
            excelentity.setReplace(isSmsReplace);
            colList.add(excelentity);
        }
        return colList;
    }
    /**
     * 导出 伪代码
     **/
    @GetMapping(value = "batchExport")
    public void batchExport(LiveUser liveUser, HttpServletResponse response){
        // 查询出导出的结果集
        List<LiveUserExportVo> liveUsers = liveUserService.batchLiveUserExport(liveUser);
        // 根据条件动态生成列信息
        List<ExcelExportEntity> beanList = dynaCol("2");
        // 导出
        ExcelUtil.exportExcelX(liveUsers, beanList,"名单.xls",  response,new ExportParams("名单", "名单"));
    }