支持pom包

com.baomidou

mybatis-plus-boot-starter

3.1.1

cn.hutool

hutool-all

4.5.10

org.apache.poi

poi-ooxml

3.17

rest代码

@GetMapping(value = "download")public voiddownload(String sqlString, HttpServletResponse response) throws IOException {

List> hashMaps =checkOrderService.invokeSql(sqlString);//Map row1 = new LinkedHashMap<>();//row1.put("姓名", "张三");//row1.put("年龄", 23);//row1.put("成绩", 88.32);//row1.put("是否合格", true);//row1.put("考试日期", DateUtil.date());//

//Map row2 = new LinkedHashMap<>();//row2.put("姓名", "李四");//row2.put("年龄", 33);//row2.put("成绩", 59.50);//row2.put("是否合格", false);//row2.put("考试日期", DateUtil.date());

ArrayList> rows =(ArrayList) hashMaps;//通过工具类创建writer，默认创建xls格式

ExcelWriter writer =ExcelUtil.getWriter();//一次性写出内容，使用默认样式，强制输出标题

writer.write(rows, true);//out为OutputStream，需要写出到的目标流//response为HttpServletResponse对象

response.setContentType("application/vnd.ms-excel;charset=utf-8");//test.xls是弹出下载对话框的文件名，不能为中文，中文请自行编码

response.setHeader("Content-Disposition","attachment;filename=test.xls");

ServletOutputStreamout=response.getOutputStream();

writer.flush(out, true);//关闭writer，释放内存

writer.close();//此处记得关闭输出Servlet流

IoUtil.close(out);//checkOrderBlh.backup2(response);

}

service

package com.mybatis.plus.service;

import com.baomidou.mybatisplus.extension.service.IService;

import com.mybatis.plus.entity.order.CheckOrder;

import java.util.HashMap;

import java.util.List;public interface CheckOrderService extends IService{

List>invokeSql(String sqlString);

}

serviceImpl

package com.mybatis.plus.service.impl;

import com.baomidou.mybatisplus.extension.service.IService;

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;

import com.mybatis.plus.entity.order.CheckOrder;

import com.mybatis.plus.mapper.order.CheckOrderMapper;

import com.mybatis.plus.service.CheckOrderService;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

import java.util.HashMap;

import java.util.List;

@Servicepublic class CheckOrderServiceImpl extends ServiceImplimplements CheckOrderService{

@AutowiredprivateCheckOrderMapper checkOrderMapper;

@Overridepublic List>invokeSql(String sqlString) {returncheckOrderMapper.invokeSql(sqlString);

}

}

mapper

package com.mybatis.plus.mapper.order;

import com.baomidou.mybatisplus.core.mapper.BaseMapper;

import com.mybatis.plus.entity.order.CheckOrder;

import org.apache.ibatis.annotations.Param;

import java.util.HashMap;

import java.util.List;

import java.util.Map;/**

*

描述：阜外盘点单表Mapper接口

*

公司：浙江瑞华康源科技有限公司

*

版权：rivamed-2019

* @author 官昌洪

* @since 2019-10-23*/

public interface CheckOrderMapper extends BaseMapper{

List> invokeSql(@Param("sqlString") String sqlString);

}

xml

${sqlString} limit1000

效果演示

浏览器url输入   localhost:8092/checkOrder/download?sqlString=select * from t_fhvc_check_order

导出excel如下

注意：存在数据库中null字段不返回的问题 添加mysql配置 call-setters-on-nulls: true 即可解决

mybatis-plus:

configuration:

log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

jdbc-type-for-null: nullcall-setters-on-nulls: truemapper-locations: classpath*:/com/mybatis/**/*Mapper.xml