1.需求

*数据库数据表导出Excle表格

*Excle数据批量新增到数据库

2.工具

工具: idea

数据库: mysql

框架：Springboot

*准备工作*：

创建springboot项目

创建项目的过程就省略了，不会的可以去看我的球员项目超详细

1.导入导出的主要依赖:poi

2.整体依赖：

<?xml version="1.0" encoding="UTF-8"?><project xmlns="/POM/4.0.0" xmlns:xsi="/2001/XMLSchema-instance"xsi:schemaLocation="/POM/4.0.0 /xsd/maven-4.0.0.xsd"><modelVersion>4.0.0</modelVersion><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.7.5</version><relativePath/> <!-- lookup parent from repository --></parent><groupId>com.springboot</groupId><artifactId>mybatisplus</artifactId><version>0.0.1-SNAPSHOT</version><name>mybatisplus</name><description>Demo project for Spring Boot</description><properties><java.version>1.8</java.version></properties><dependencies><dependency><groupId>com.baomidou</groupId><artifactId>mybatis-plus-boot-starter</artifactId><version>3.5.2</version></dependency><dependency><groupId>com.alibaba</groupId><artifactId>druid-spring-boot-starter</artifactId><version>1.2.15</version></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-thymeleaf</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>com.mysql</groupId><artifactId>mysql-connector-j</artifactId><scope>runtime</scope></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><dependency><groupId>org.apache.poi</groupId><artifactId>poi</artifactId><version>3.17</version></dependency><dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml</artifactId><version>4.1.2</version></dependency></dependencies><build><plugins><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId><configuration><excludes><exclude><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId></exclude></excludes></configuration></plugin></plugins></build><repositories><repository><id>spring-milestones</id><name>Spring Milestones</name><url>https://repo.spring.io/milestone</url><snapshots><enabled>false</enabled></snapshots></repository><repository><id>spring-snapshots</id><name>Spring Snapshots</name><url>https://repo.spring.io/snapshot</url><releases><enabled>false</enabled></releases></repository></repositories><pluginRepositories><pluginRepository><id>spring-milestones</id><name>Spring Milestones</name><url>https://repo.spring.io/milestone</url><snapshots><enabled>false</enabled></snapshots></pluginRepository><pluginRepository><id>spring-snapshots</id><name>Spring Snapshots</name><url>https://repo.spring.io/snapshot</url><releases><enabled>false</enabled></releases></pluginRepository></pluginRepositories></project>

3.yaml配置

spring:datasource:url: jdbc:mysql://localhost:3306/aac?serverTimezone=GMT%2B8username: rootpassword: rootdriver-class-name: com.mysql.cj.jdbc.Driverthymeleaf:cache: falsesuffix=: .htmlprefix: classpath:/templates/# type: com.zaxxer.hikari.HikariDataSourcejdbc:template:query-timeout: 3mybatis-plus:configuration:log-impl: org.apache.ibatis.logging.stdout.StdOutImpl

3.数据库数据导出Excle表格

1.数据库表结构

2..总体结构

准备实体类goods（我的实体类是Mybatisplus生成的，我就往上面加注解就行了）

可以自动生成很多东西,需要下载mybatisx

连接数据库后

手写也没问题

@TableName(value ="goods")对应的是你的数据库表@Value属性是匹配Excle表格的标头名称(导入准备的)导出导入共用一个实体类

3.controller层

@RequestMapping("/ExcelDownload")public void excelDownload(HttpServletResponse response) throws IOException {//表头数据String[] header = {"id", "数量", "姓名", "单价", "物品类型"};//声明一个工作簿HSSFWorkbook workbook = new HSSFWorkbook();//生成一个表格，设置表格名称为"学生表"HSSFSheet sheet = workbook.createSheet("物品表");//设置表格列宽度为10个字节sheet.setDefaultColumnWidth(10);//创建第一行表头HSSFRow headrow = sheet.createRow(0);//遍历添加表头(下面模拟遍历学生，也是同样的操作过程)for (int i = 0; i < header.length; i++) {//创建一个单元格HSSFCell cell = headrow.createCell(i);//创建一个内容对象HSSFRichTextString text = new HSSFRichTextString(header[i]);//将内容对象的文字内容写入到单元格中cell.setCellValue(text);}//***********************************//拿到数据List<Goods> goods = goodsService.getAllGoodsList();for (int i = 0; i < goods.size(); i++) {HSSFRow row = sheet.createRow(i + 1);Goods good = goods.get(i);HSSFCell cell = null;String[] names = {Math.toIntExact(good.getId()) + "",good.getCount() + "",good.getName() + "",good.getPrice() + "",good.getType().getTyname() + ""};for (int k = 0; k < names.length; k++) {cell = row.createCell(k);//拿到属性值HSSFRichTextString text = new HSSFRichTextString(names[k]);cell.setCellValue(text);}}//*****************************************//准备将Excel的输出流通过response输出到页面下载//八进制输出流response.setContentType("application/octet-stream");//这后面可以设置导出Excel的名称，此例中名为student.xlsresponse.setHeader("Content-disposition", "attachment;filename=student.xls");//刷新缓冲response.flushBuffer();//workbook将Excel写入到response的输出流中，供页面下载workbook.write(response.getOutputStream());}

//****** 中间的代码就是从数据库拿值出来放到表格中

//拿到数据

List<Goods> goods = goodsService.getAllGoodsList();

如果想让controller层看起来干净点 没事 我把他封装了一个工具类

两者选其一就行

package com.springboot.mybatisplus.config;import org.apache.poi.hssf.usermodel.*;import org.apache.poi.ss.usermodel.*;import org.apache.poi.xssf.usermodel.XSSFWorkbook;import javax.servlet.http.HttpServletResponse;import java.beans.PropertyDescriptor;import java.io.IOException;import java.lang.reflect.Field;import java.text.DateFormat;import java.text.SimpleDateFormat;import java.util.Date;import java.util.List;public class ExcelUtil {/*** Excel表格导出* @param response HttpServletResponse对象* @param excelData Excel表格的数据，封装为List<List<String>>* @param sheetName sheet的名字* @param fileName 导出Excel的文件名* @param columnWidth Excel表格的宽度，建议为15* @throws IOException 抛IO异常*/public static void exportExcel(HttpServletResponse response,List<List<String>> excelData,String sheetName,String fileName,int columnWidth) throws IOException {//声明一个工作簿HSSFWorkbook workbook = new HSSFWorkbook();//生成一个表格，设置表格名称HSSFSheet sheet = workbook.createSheet(sheetName);//设置表格列宽度sheet.setDefaultColumnWidth(columnWidth);//写入List<List<String>>中的数据int rowIndex = 0;for(List<String> data : excelData){//创建一个row行，然后自增1HSSFRow row = sheet.createRow(rowIndex++);//遍历添加本行数据for (int i = 0; i < data.size(); i++) {//创建一个单元格HSSFCell cell = row.createCell(i);//创建一个内容对象HSSFRichTextString text = new HSSFRichTextString(data.get(i));//将内容对象的文字内容写入到单元格中cell.setCellValue(text);}}//准备将Excel的输出流通过response输出到页面下载//八进制输出流response.setContentType("application/octet-stream");//设置导出Excel的名称response.setHeader("Content-disposition", "attachment;filename=" + fileName);//刷新缓冲response.flushBuffer();//workbook将Excel写入到response的输出流中，供页面下载该Excel文件workbook.write(response.getOutputStream());//关闭workbookworkbook.close();}}

4.service接口层

5.service实现类

package com.springboot.mybatisplus.service.impl;import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;import com.springboot.mybatisplus.pojo.Goods;import com.springboot.mybatisplus.service.GoodsService;import com.springboot.mybatisplus.mapper.GoodsMapper;import org.apache.ibatis.annotations.Mapper;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import java.util.List;/****/@Servicepublic class GoodsServiceImpl extends ServiceImpl<GoodsMapper, Goods>implements GoodsService{@Autowiredprivate GoodsMapper goodsMapper;@Overridepublic int addAllGoods(List<Goods> list) {for (int i = 0; i <list.size() ; i++) {if (list.get(i)==null){continue;}System.out.println(getBaseMapper().insert(list.get(i)));}return 1;}@Overridepublic List<Goods> getAllGoodsList() {return goodsMapper.getAll();}}

addAllGoods(List<Goods> list):是导入给数据库批量新增的方法，用的是Mybatisplus自己封装的新增的方法

List<Goods> getAllGoodsList():是自己写的导出从数据库两表查询的方法

6.mapper接口层

7.mapper.xml

getAll写的就是两表查询

然后手动映射(这个也是Mybatisplus自动生成的)

页面：html+thymeleaf

就ok了可以通过地址导出了

4.Excle数据批量新增到数据库

1.实体类是一样的

2.service接口层 （和上面一样的）

3.service实现类（和上面一样的）

package com.springboot.mybatisplus.service.impl;import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;import com.springboot.mybatisplus.pojo.Goods;import com.springboot.mybatisplus.service.GoodsService;import com.springboot.mybatisplus.mapper.GoodsMapper;import org.apache.ibatis.annotations.Mapper;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Service;import java.util.List;/****/@Servicepublic class GoodsServiceImpl extends ServiceImpl<GoodsMapper, Goods>implements GoodsService{@Autowiredprivate GoodsMapper goodsMapper;@Overridepublic int addAllGoods(List<Goods> list) {for (int i = 0; i <list.size() ; i++) {if (list.get(i)==null){continue;}System.out.println(getBaseMapper().insert(list.get(i)));}return 1;}@Overridepublic List<Goods> getAllGoodsList() {return goodsMapper.getAll();}}

4.然后写一个工具类

package com.springboot.mybatisplus.config;import org.apache.poi.hssf.usermodel.HSSFWorkbook;import org.apache.poi.ss.usermodel.*;import org.apache.poi.xssf.usermodel.XSSFWorkbook;import org.springframework.beans.factory.annotation.Value;import javax.swing.text.DateFormatter;import java.io.InputStream;import java.lang.reflect.Field;import java.math.BigDecimal;import java.text.SimpleDateFormat;import java.time.LocalDateTime;import java.time.format.DateTimeFormatter;import java.util.ArrayList;import java.util.Date;import java.util.List;import static java.sql.Types.BOOLEAN;import static java.sql.Types.NUMERIC;import static org.apache.poi.ss.usermodel.DataValidationConstraint.ValidationType.FORMULA;import static org.apache.tomcat.util.bcel.classfile.ElementValue.STRING;public class ExcelImport {//上传的是以.xls后缀的private final static String excelL = ".xls";//上传的是以.xlsx后缀的private final static String excelU = ".xlsx";public static List<List<Object>> getListByExcel(InputStream in, String fileName) throws Exception {//创建 list 模拟Excel表结构List<List<Object>> list = null;//创建Excel工作薄Workbook work = getWorkbook(in, fileName);if (null == work) {throw new Exception("创建Excel工作薄为空！");}Sheet sheet = null; //页数Row row = null; //行数Cell cell = null; //列数list = new ArrayList<List<Object>>();//遍历Excel中所有的sheet页for (int i = 0; i < work.getNumberOfSheets(); i++) {sheet = work.getSheetAt(i);if (sheet == null) {continue;}//遍历当前sheet中的所有行for (int j = sheet.getFirstRowNum(); j <= sheet.getLastRowNum(); j++) {row = sheet.getRow(j);if (row == null) {continue;}//遍历所有的列List<Object> li = new ArrayList<Object>();for (int y = row.getFirstCellNum(); y < row.getLastCellNum(); y++) {//获取第i页第j行第y列的值//Cannot get a STRING value from a NUMERIC cell//poi导入excel表格数据时报java.lang.IllegalStateException: Cannot get a STRING value from a NUMERIC cell异常是因为在读取cell单元格字符串时，有number类型的数据，因此需要把它转化为纯String类型//在number类型转化为String类型的过程中造成了Cannot get a STRING value from a NUMERIC cell这样的问题，因此需要在读取excel单元格数据转化之前设置单元格类型为String// cell = row.getCell(y);// li.add(getValue(cell));String cellValue=new DataFormatter().formatCellValue(row.getCell(y));li.add(cellValue);}list.add(li);}}return list;}public static Workbook getWorkbook(InputStream inStr, String fileName) throws Exception {Workbook wb = null;//获取Excel后缀String fileType = fileName.substring(fileName.lastIndexOf("."));//跟据后缀创建工作簿if (excelL.equals(fileType)) {wb = new HSSFWorkbook(inStr); //-} else if (excelU.equals(fileType)) {wb = new XSSFWorkbook(inStr); //+} else {throw new Exception("解析的文件格式有误！");}return wb;}public static String getValue(Cell cell) {String value = "";if (null == cell) {return value;}switch (cell.getCellType()) {//数值型case NUMERIC:if (DateUtil.isCellDateFormatted(cell)) {//如果是date类型则 ，获取该cell的date值Date date = DateUtil.getJavaDate(cell.getNumericCellValue());SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");value = format.format(date);;} else {// 纯数字BigDecimal big = new BigDecimal(cell.getNumericCellValue());value = big.toString();//解决1234.0 去掉后面的.0if (null != value && !"".equals(value.trim())) {String[] item = value.split("[.]");if (1 < item.length && "0".equals(item[1])) {value = item[0];}}}break;//字符串类型case STRING://如果是string类型进行下划线转驼峰处理value = cell.getStringCellValue();break;// 公式类型case FORMULA://读公式计算值value = String.valueOf(cell.getNumericCellValue());if (value.equals("NaN")) {// 如果获取的数据值为非法值,则转换为获取字符串value = cell.getStringCellValue();}break;// 布尔类型case BOOLEAN:value = " " + cell.getBooleanCellValue();break;default:value = cell.getStringCellValue();}if ("null".endsWith(value.trim())) {value = "";}return value;}public static void setFileValueByFieldName(Object object, String fieldName, Object val) {//获取object类的所有属性Field[] fields = object.getClass().getDeclaredFields();try {//对所有属性进行遍历for (int i = 0; i < fields.length; i++) {//获取第i个属性Field field = fields[i];//如果Excel的某一列的列名(fieldName)与//在第i个属性上面添加的@Value注解的value一样，进行下面的操作if (fieldName.equals(field.getAnnotation(Value.class).value())) {Class type = field.getType();if (fieldName.equals("id")){continue;}//如果field为私有属性，也可以对它进行操作field.setAccessible(true);//获取该属性的数据类型，如果是Integer类型的if (field.getType()==Integer.class) {field.set(object, Integer.valueOf(val.toString()));//如果时LocalDateTime类型的} else if (field.getType()==double.class) {field.set(object, Double.valueOf(val.toString()));//如果时LocalDateTime类型的} else if (type== int.class) {//把val转成Integer存到该属性里面field.set(object, Integer.valueOf(val.toString()));} else if (field.getType()==long.class) {field.set(object, Long.valueOf(val.toString()));//如果时LocalDateTime类型的} else if (field.getType() == LocalDateTime.class) {//先把他格式化DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");LocalDateTime time = LocalDateTime.parse(val.toString(), formatter);field.set(object, time);//如果其他类型的直接存} else {field.set(object, val);}return;}}} catch (Exception e) {e.printStackTrace();}}}

setFileValueByFieldName（实体类Object，Excle表格的标头fileName，要注入的值var）在该方法进行属性类型判定赋值

5.controller层

package com.springboot.mybatisplus.controller;import com.springboot.mybatisplus.config.ExcelImport;import com.springboot.mybatisplus.pojo.Goods;import com.springboot.mybatisplus.service.impl.GoodsServiceImpl;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.PostMapping;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestParam;import org.springframework.web.bind.annotation.ResponseBody;import org.springframework.web.multipart.MultipartFile;import java.io.File;import java.io.FileInputStream;import java.util.ArrayList;import java.util.List;@Controllerpublic class StudentController {@AutowiredGoodsServiceImpl goodService;@RequestMapping("/upload")@ResponseBodypublic String uploadFile(@RequestParam("file") MultipartFile file) throws Exception {try {// 上传文件路径String filePath = "E:\\doc\\sdfsdf";// 为了防止文件名冲突，获取当前时间+文件原名生成新的文件名String fileName = System.currentTimeMillis() + file.getOriginalFilename();// 上传文件File f = new File(filePath + fileName);file.transferTo(f);fileName = filePath + fileName;//输入流，获取刚刚上传文件转成输入流FileInputStream fileInputStream = new FileInputStream(new File(fileName));//定义一个list变量，模拟excel结构List<List<Object>> list = ExcelImport.getListByExcel(fileInputStream, fileName);//定义firstRows变量，用来获取第一行，就是标题，每列名字List<Object> firstRows = null;//定义studentList变量，用来存储文件内容(学生信息)List<Goods> studentList = new ArrayList<>();//如果 list 不为空，大小大于0则获取第一行存到firstRows 里面if (list != null && list.size() > 0) {firstRows = list.get(0);} else {//否则返回 failurereturn "表格数据为空";}//对list进行遍历，因为第一行是标题，不用存到数据库，所以从第二行开始遍历for (int i = 1; i < list.size(); i++) {//获取第i行数据List<Object> rows = list.get(i);//定义goods遍历，存储第i行数据Goods good = new Goods();//对第i行数据进行遍历，//从1开始是因为新增不能有idfor (int j = 1; j < rows.size(); j++) {//获取第i行第j列数据，存到cellVal 变量里面String cellVal = (String) rows.get(j);//调用setFileValueByFieldName函数，把数据存到student对应的属性里面ExcelImport.setFileValueByFieldName(good, firstRows.get(j).toString().trim(), cellVal);}//把student变量加到studentListstudentList.add(good);}//调用批量插入方法，把数据存到数据库int o= goodService.addAllGoods(studentList);if (o != 0) {return "成功了";} else {return "导入失败";}} catch (Exception e) {return "报错了: "+e.getMessage();}}}

这边id是自增列，所以不把id新增进去，所以 int =i

6.前端导入页面

<!DOCTYPE html><html lang="en" xmlns:th=""><head><meta charset="UTF-8"><title>导入Excel</title></head><body><h1>选择Excel</h1><form th:action="@{/upload}" method="post" enctype="multipart/form-data"><!-- name 的值与@RequestParam的值相同--><input type="file" name="file"/><br/><input type="submit" value="上传"/><br/></form></body></html>

5.效果

点击导出后

**导入

准备表：

选择Excle表后

点击提交

查看数据库

总结：制作不易，如果帮助到你 请点赞收藏支持一下

如果新增的只有name或者新增不全面

看一下实体类的注解

还有看一下工具类的这个地方有没有判断你实体类属性的数据类型，没有的话照着写一个

如果还有纰漏请及时告知 感谢观看