Spring Boot整合EasyExcel(完整版包含上传解析excel和下载模板)

网友投稿 1232 2023-02-25

Spring Boot整合EasyExcel(完整版包含上传解析excel和-模板)

Spring Boot整合EasyExcel(完整版包含上传解析excel和-模板)

1. 加入依赖

com.alibaba

easyexcel

2.2.7

2. 对读取excel内容(批量添加)

@PostMapping("plUpdate")

public R plUpdate(@RequestParam("filename") MultipartFile file) throws IOException {

//String Originalfilename = file.getOriginalFilename();

// String fileName = file.getName();

// System.out.println("orname="+Originalfilename+";"+"filename"+file.getName());

// 获取文件全名

String fileName = file.getOriginalFilename();

//设置文件路径

String templatePath = "G:/excel/";

File dest0 = new File(templatePath);

File dest = new File(dest0, fileName);

//文件上传-覆盖

try {

// 检测是否存在目录

if (!dest0.getParentFile().exists()) {

dest0.getParentFile().mkdirs();

//检测文件是否存在

}

if (!dest.exists()) {

dest.mkdirs();

}

file.transferTo(dest);

} catch (Exception e) {

return R.error();

}

String finameUrl = templatePath+fileName;

ExcelReader excelReader = null;

try {

//TeacherExcel.class对应的是和模板一样的实体类,

//eduTeacherService对应持久层的接口

excelReader = EasyExcel.read(finameUrl, TeacherExcel.class, new DemoDataListener(eduTeacherService)).build();

ReadSheet readSheet = EasyExcel.readSheet(0).build();

excelReader.read(readSheet);

} finally {

if (excelReader != null) {

// 这里千万别忘记关闭,读的时候会创建临时文件,到时磁盘会崩的

excelReader.finish();

}

}

return R.ok();

}

创建一个监听类:

package com.atguigu.excel;

import com.alibaba.excel.context.AnalysisContext;

import com.alibaba.excel.event.AnalysisEventListener;

import com.atguigu.eduservice.entity.EduTeacher;

import com.atguigu.eduservice.entity.vo.TeacherExcel;

import com.atguigu.eduservice.service.EduTeacherService;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import java.util.ArrayList;

import java.util.List;

// 有个很重要的点 DemoDataListener 不能被spring管理,要每次读取excel都要new,然后里面用到spring可以构造方法传进去

public class DemoDataListener extends AnalysisEventListener {

private static final Logger LOGGER = LoggerFactory.getLogger(DemoDataListener.class);

//这里写持久层的类

private EduTeacherService eduTeacherService;

/**

* 如果使用了spring,请使用这个构造方法。每次创建Listener的时候需要把spring管理的类传进来

*

* @param eduTeacherService

*/

public DemoDataListener( EduTeacherService eduTeacherService) {

//进行持久层的类

this.eduTeacherService = eduTeacherService;

}

/**

* 每隔5条存储数据库,实际使用中可以3000条,然后清理list ,方便内存回收

*/

private static final int BATCH_COUNT = 5;

List list = new ArrayList();

/**

* 假设这个是一个DAO,当然有业务逻辑这个也可以是一个service。当然如果不用存储这个对象没用。

*/

//private DemoDAO demoDAO;

public DemoDataListener() {

// 这里是demo,所以随便new一个。实际使用如果到了spring,请使用下面的有参构造函数

//demoDAO = new DemoDAO();

}

/**

* 如果使用了spring,请使用这个构造方法。每次创建Listener的时候需要把spring管理的类传进来

*

* @param demoDAO

*/

/* public DemoDataListener(DemoDAO demoDAO) {

this.demoDAO = demoDAO;

}*/

/**

* 这个每一条数据解析都会来调用

*

* @param data

* one row value. Is is same as {@link AnalysisContext#readRowHolder()}

* @param context

*/

@Override

public void invoke(TeacherExcel data, AnalysisContext context) {

LOGGER.info("解析到一条数据:{}",data.toString());

list.add(data);

// 达到BATCH_COUNT了,需要去存储一次数据库,防止数据几万条数据在内存,容易OOM

}

/**

* 所有数据解析完成了 都会来调用

*

* @param context

*/

@Override

public void doAfterAllAnalysed(AnalysisContext context) {

// 这里也要保存数据,确保最后遗留的数据也存储到数据库

saveData();

LOGGER.info("所有数据解析完成!");

}

/**

* 加上存储数据库

*/

private void saveData() {

LOGGER.info("{}条数据,开始存储数据库!", list.size());

//因为我excel模板的实体和插入数据库实体的类不一样,所以需要进行转化

for (int i =0;i

EduTeacher teacher = new EduTeacher();

teacher.setLevel(list.get(i).getLevel());

teacher.setCareer(list.get(i).getCareer());

teacher.setName(list.get(i).getName());

teacher.setSort(list.get(i).getSort());

teacher.setIntro(list.get(i).getIntro());

boolean save = eduTeacherService.save(teacher);

if (save){

System.out.println("第"+i+"添加成功");

}

}

}

}

例如我的excel模板是:

实体类:

字段上ExcelProperty的注解可以使用index声明字段在模板中的顺序,使用value声明模板各个字段的名称。

例如:

@ExcelProperty(value = “讲师简介”,index = 1)

private String intro;

模板的实体类要和excel字段一样对应,不然会出错

效果:

3. 模板-:

创建一个工具类:

package com.atguigu.eduservice.config;

import com.alibaba.excel.EasyExcel;

import com.alibaba.excel.support.ExcelTypeEnum;

import com.alibaba.excel.write.metadata.style.WriteCellStyle;

import com.alibaba.excel.write.style.HorizontalCellStyleStrategy;

import org.apache.poi.ss.usermodel.HorizontalAlignment;

import javax.servlet.http.HttpServletResponse;

import java.io.OutputStream;

import java-.URLEncoder;

import java.util.List;

/**

* @author linjiazeng

* @version 1.0

* @date 2020/12/28 22:29

**/

public class ExcelUtil {

/**

* 导出

* @param response

* @param data

* @param fileName

* @param sheetName

* @param clazz

* @throws Exception

*/

public static void writeExcel(HttpServletResponse response, List extends Object> data, String fileName, String sheetName, Class clazz) throws Exception {

//表头样式

WriteCellStyle headWriteCellStyle = new WriteCellStyle();

//设置表头居中对齐

headWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.CENTER);

//内容样式

WriteCellStyle contentWriteCellStyle = new WriteCellStyle();

//设置内容靠左对齐

contentWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.LEFT);

HorizontalCellStyleStrategy horizontalCellStyleStrategy = new HorizontalCellStyleStrategy(headWriteCellStyle, contentWriteCellStyle);

EasyExcel.write(getOutputStream(fileName, response), clahttp://zz).excelType(ExcelTypeEnum.XLSX).sheet(sheetName).registerWriteHandler(horizontalCellStyleStrategy).doWrite(data);

}

private static OutputStream getOutputStream(String fileName, HttpServletResponse response) throws Exception {

fileName = URLEncoder.encode(fileName, "UTF-8");

response.setContentType("application/vnd.ms-excel");

response.setCharacterEncoding("utf8");

response.setHeader("Content-Disposition", "attachment;filename=" + fileName + ".xlsx");

response.addHeader("Access-Control-Expose-Headers", "Content-disposition");

return response.getOutputStream();

}

}

调用工具类-模板

/*-模板*/

@GetMapping("/download/template")

public void pWOHLMtHdownloadTemplate(HttpServletResponse response){

String fileName = "导入讲师模板";

String sheetName="导入讲师模板";

List teacherExcelList = new ArrayList<>();

TeacherExcel teacherExcel = new TeacherExcel();

teacherExcel.setName("ljz");

teacherExcel.setIntro("清华毕业,高材生");

teacherExcel.setCareer("资深讲师");

teacherExcel.setSort(1);

teacherExcel.setLevel(1);

teacherExcelList.add(teacherExcel);

try {

//TeacherExcel.class对应你的模板类

//teacherExcelLihttp://st模板的例子

//也可以使用这种方式导出你查询出数据excel文件

ExcelUtil.writeExcel(response,teacherExcelList,fileName,sheetName,TeacherExcel.class);

} catch (Exception e) {

System.out.println(e.getCause());

}

}

效果:

有问题可以互相交流,也可以去EasyExcel官网学习

EduTeacher teacher = new EduTeacher();

teacher.setLevel(list.get(i).getLevel());

teacher.setCareer(list.get(i).getCareer());

teacher.setName(list.get(i).getName());

teacher.setSort(list.get(i).getSort());

teacher.setIntro(list.get(i).getIntro());

boolean save = eduTeacherService.save(teacher);

if (save){

System.out.println("第"+i+"添加成功");

}

}

}

}

例如我的excel模板是:

实体类:

字段上ExcelProperty的注解可以使用index声明字段在模板中的顺序,使用value声明模板各个字段的名称。

例如:

@ExcelProperty(value = “讲师简介”,index = 1)

private String intro;

模板的实体类要和excel字段一样对应,不然会出错

效果:

3. 模板-:

创建一个工具类:

package com.atguigu.eduservice.config;

import com.alibaba.excel.EasyExcel;

import com.alibaba.excel.support.ExcelTypeEnum;

import com.alibaba.excel.write.metadata.style.WriteCellStyle;

import com.alibaba.excel.write.style.HorizontalCellStyleStrategy;

import org.apache.poi.ss.usermodel.HorizontalAlignment;

import javax.servlet.http.HttpServletResponse;

import java.io.OutputStream;

import java-.URLEncoder;

import java.util.List;

/**

* @author linjiazeng

* @version 1.0

* @date 2020/12/28 22:29

**/

public class ExcelUtil {

/**

* 导出

* @param response

* @param data

* @param fileName

* @param sheetName

* @param clazz

* @throws Exception

*/

public static void writeExcel(HttpServletResponse response, List extends Object> data, String fileName, String sheetName, Class clazz) throws Exception {

//表头样式

WriteCellStyle headWriteCellStyle = new WriteCellStyle();

//设置表头居中对齐

headWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.CENTER);

//内容样式

WriteCellStyle contentWriteCellStyle = new WriteCellStyle();

//设置内容靠左对齐

contentWriteCellStyle.setHorizontalAlignment(HorizontalAlignment.LEFT);

HorizontalCellStyleStrategy horizontalCellStyleStrategy = new HorizontalCellStyleStrategy(headWriteCellStyle, contentWriteCellStyle);

EasyExcel.write(getOutputStream(fileName, response), clahttp://zz).excelType(ExcelTypeEnum.XLSX).sheet(sheetName).registerWriteHandler(horizontalCellStyleStrategy).doWrite(data);

}

private static OutputStream getOutputStream(String fileName, HttpServletResponse response) throws Exception {

fileName = URLEncoder.encode(fileName, "UTF-8");

response.setContentType("application/vnd.ms-excel");

response.setCharacterEncoding("utf8");

response.setHeader("Content-Disposition", "attachment;filename=" + fileName + ".xlsx");

response.addHeader("Access-Control-Expose-Headers", "Content-disposition");

return response.getOutputStream();

}

}

调用工具类-模板

/*-模板*/

@GetMapping("/download/template")

public void pWOHLMtHdownloadTemplate(HttpServletResponse response){

String fileName = "导入讲师模板";

String sheetName="导入讲师模板";

List teacherExcelList = new ArrayList<>();

TeacherExcel teacherExcel = new TeacherExcel();

teacherExcel.setName("ljz");

teacherExcel.setIntro("清华毕业,高材生");

teacherExcel.setCareer("资深讲师");

teacherExcel.setSort(1);

teacherExcel.setLevel(1);

teacherExcelList.add(teacherExcel);

try {

//TeacherExcel.class对应你的模板类

//teacherExcelLihttp://st模板的例子

//也可以使用这种方式导出你查询出数据excel文件

ExcelUtil.writeExcel(response,teacherExcelList,fileName,sheetName,TeacherExcel.class);

} catch (Exception e) {

System.out.println(e.getCause());

}

}

效果:

有问题可以互相交流,也可以去EasyExcel官网学习

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