使用hutool工具进行导入导出excel表格

 <!--hutool-->
        <dependency>
            <groupId>cn.hutool</groupId>
            <artifactId>hutool-all</artifactId>
            <version>5.7.20</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>4.1.2</version>
        </dependency>

  //表格导出接口
    @GetMapping("/export")
    public void export(HttpServletResponse response) throws IOException {
        //查询所有用户
        List<User> list= userService.list();
        //在内存操作，写到浏览器
        ExcelWriter writer= ExcelUtil.getWriter(true);
 
        //自定义标题别名
        writer.addHeaderAlias("username","用户名");
        writer.addHeaderAlias("password","密码");
        writer.addHeaderAlias("nickname","昵称");
        writer.addHeaderAlias("email","邮箱");
        writer.addHeaderAlias("phone","电话");
        writer.addHeaderAlias("address","地址");
        writer.addHeaderAlias("createTime","创建时间");
 
        //默认配置
        writer.write(list,true);
        //设置content—type
        response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet;charset:utf-8");
 
        //设置标题
        String fileName= URLEncoder.encode("用户信息","UTF-8");
        //Content-disposition是MIME协议的扩展，MIME协议指示MIME用户代理如何显示附加的文件。
        response.setHeader("Content-Disposition","attachment;filename="+fileName+".xlsx");
        ServletOutputStream outputStream= response.getOutputStream();
 
        //将Writer刷新到OutPut
        writer.flush(outputStream,true);
        outputStream.close();
        writer.close();
    }

  //点击函数exp, 导出表格
            exp(){
                window.open("http://localhost:9090/user/export")
            }

/**
     * 导入excel
     * @param file
     */
    @PostMapping("/import")
    public void importExcel(MultipartFile file) throws IOException {
        //1.第一种 头必须和实体(英文)一样
        //文件处理成io流
        InputStream in = file.getInputStream();
//        //io流给ExcelReader
        ExcelReader excelReader=ExcelUtil.getReader(in);
//        //读取数据且转化为list
//        List<User> list = excelReader.readAll(User.class);
 
        //2.第二种导入方式
        //忽略第一行头(第一行是中文的情况),直接读取表的内容
        List<List<Object>> list = excelReader.read(1);
        List<User> listUser = CollUtil.newArrayList();
        for (List<Object> row: list) {
            User user=new User();
            user.setUsername(row.get(0).toString());
            user.setPassword(row.get(1).toString());
            user.setNickname(row.get(2).toString());
            user.setNickname(row.get(3).toString());
            user.setPhone(row.get(4).toString());
            user.setAddress(row.get(5).toString());
            listUser.add(user);
//            ****类似一一对应****
        }
        //批量注册进数据库
        userService.saveBatch(listUser);
    }

      <el-upload action="http://localhost:9090/user/import"  
                    :show-file-list="false" accept="xlsx" 
                    :on-success="handleImportSuccess" 
                    style="display: inline-block;margin-right: 5px">
           <el-button type="primary">导入 <i class="el-icon-bottom"></i></el-button>
      </el-upload>

//导入,钩子函数进行页面的提示跟成功后页面的刷新
            handleImportSuccess(){
                this.$message.success("导入成功")
                this.load();
            }