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2023-02-25
Spring Boot整合EasyExcel(完整版包含上传解析excel和-模板)
1. 加入依赖
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
/**
* 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 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
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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