java基于poi最简单最详细的Excel导入导出功能
一、Excel的导入导出工具类
1、Excel导出工具类
package com.djw.excel.utils;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
/**
* @Author djw
* @Description //TODO
* @Date 2018/9/5 15:52
*/
public class ExcelExport {
/**
* 导出Excel
* @param sheetName sheet名称
* @param title 标题
* @param values 内容
* @return
*/
public static HSSFWorkbook createWorkbook(String sheetName,String []title,String [][]values){
// 第一步，创建一个HSSFWorkbook，对应一个Excel文件
HSSFWorkbook wb = new HSSFWorkbook();
// 第二步，在workbook中添加一个sheet,对应Excel文件中的sheet
HSSFSheet sheet = wb.createSheet(sheetName);
// 第三步，在sheet中添加表头第0行,注意老版本poi对Excel的行数列数有限制
HSSFRow row = sheet.createRow(0);
// 第四步，创建单元格，并设置值表头 设置表头居中
HSSFCellStyle style = wb.createCellStyle();
style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 创建一个居中格式
//声明列对象
HSSFCell cell = null;
//创建标题
for(int i=0;i2、Excel导入工具类
package com.djw.excel.utils;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import java.io.File;
import java.io.FileInputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* @Author djw
* @Description //TODO
* @Date 2018/9/5 16:16
*/
public class ExcelImport {
/**
* @param dest 表格文件
* @param cellLength 一行多少个单元格
* @return 返回list集合
* @throws Exception
*/
public static List> read(File dest, Integer cellLength) throws Exception{
Workbook wookbook = null;
FileInputStream fis = null;
int cellType = 1;
try {
fis = new FileInputStream(dest);
//用HSSF来处理，有异常即为xlsx格式，用XSSF处理
wookbook = new HSSFWorkbook(fis);//得到工作簿
cellType = HSSFCell.CELL_TYPE_STRING;
} catch (Exception e) {
try {
fis = new FileInputStream(dest);//这里不创建输入流就会报错stream close
wookbook = new XSSFWorkbook(fis);
cellType = XSSFCell.CELL_TYPE_STRING;
} catch (Exception e1) {
//返回文件格式错误异常
throw new Exception("This file is not in excel format");
}//得到工作簿
} finally {
fis.close();
}
//得到一个工作表
Sheet sheet = wookbook.getSheetAt(0);
//获得数据的总行数
int totalRowNum = sheet.getLastRowNum();
//要获得属性
List> list = new ArrayList>();
Map map = null;
//获得所有数据
//从第x行开始获取
for(int x = 1 ; x <= totalRowNum ; x++){
map = new HashMap();
//获得第i行对象
Row row = sheet.getRow(x);
//如果一行里的所有单元格都为空则不放进list里面
int a = 0;
for(int y=0;y 二、controller层的具体操作方法
1、为了演示，首先创建了一个user实体类
package com.djw.excel.entiy;
/**
* @Author djw
* @Description 演示所创建的对象
* @Date 2018/9/5 14:52
*/
public class User {
Integer userId;
String userName;
String sex;
Integer age;
String school;
public Integer getUserId() {
return userId;
}
public void setUserId(Integer userId) {
this.userId = userId;
}
public String getUserName() {
return userName;
}
public void setUserName(String userName) {
this.userName = userName;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String getSchool() {
return school;
}
public void setSchool(String school) {
this.school = school;
}
@Override
public String toString() {
return "User{" +
"userId=" + userId +
", userName='" + userName + '\'' +
", sex='" + sex + '\'' +
", age=" + age +
", school='" + school + '\'' +
'}';
}
}
2、具体实现方法
package com.djw.excel.controller;
import com.djw.excel.entiy.User;
import com.djw.excel.utils.ExcelExport;
import com.djw.excel.utils.ExcelImport;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
@RestController
@RequestMapping("excel")
@Api(value = "ecxel相关操作",description = "excel相关操作")
public class ExcelController {
// @GetMapping("getExcel")
// @ApiOperation(value = "导出Excel",notes = "导出Excel")
// public void getExcel(HttpServletResponse response) {
// //excel标题
// String[] title = {"名称", "性别", "年龄", "学校", "班级"};
// //excel文件名
// String fileName = "学生信息表";
// String sheetName = "学生信息表";
// String[][] values = {{"张三", "男", "18", "家里蹲大学", "14电信1班"}, {"张三", "男", "18", "家里蹲大学", "14电信1班"}, {"张三", "男", "18", "家里蹲大学", "14电信1班"},
// {"张三", "男", "18", "家里蹲大学", "14电信1班"}, {"张三", "男", "18", "家里蹲大学", "14电信1班"}, {"张三", "男", "18", "家里蹲大学", "14电信1班"},
// {"张三", "男", "18", "家里蹲大学", "14电信1班"}};
// //创建HSSFWorkbook
// HSSFWorkbook wb = ExcelUtil.createWorkbook(sheetName, title, values);
// //响应到客户端
// try {
// //设置编码、输出文件格式
// response.reset();
// fileName = java.net.URLEncoder.encode(fileName, "UTF-8");
// response.setContentType("application/vnd.ms-excel;charset=UTF-8");
// response.setHeader("Content-Disposition", "attachment;filename=" + fileName + ".xls");
// OutputStream os = response.getOutputStream();
// wb.write(os);
// os.flush();
// os.close();
// } catch (Exception e) {
// e.printStackTrace();
// }
// }
@GetMapping("createExcel")
@ApiOperation(value = "创建excel表格",notes = "创建Excel表格")
public void createExcel(HttpServletResponse response){
//添加测试数据
List userList = new ArrayList<>();
for (int i = 0; i < 20; i++) {
User user = new User();
user.setUserId(i);
user.setUserName("张三"+i);
user.setSex("男");
user.setAge(i);
user.setSchool("学校"+i);
userList.add(user);
}
//excel标题
String[] title = {"id", "姓名", "性别", "年龄", "学校"};
String[][] objects = new String[userList.size()][title.length];
for (int i = 0; i < userList.size(); i++) {
User user = userList.get(i);
objects[i][0] = String.valueOf(user.getUserId());
objects[i][1] = user.getUserName();
objects[i][2] = user.getSex();
objects[i][3] = String.valueOf(user.getAge());
objects[i][4] = user.getSchool();
}
String fileName = "学生信息表";
//创建HSSFWorkbook
HSSFWorkbook wb = ExcelExport.createWorkbook(fileName, title, objects);
//响应到客户端
try {
//设置编码、输出文件格式
response.reset();
fileName = java.net.URLEncoder.encode(fileName, "UTF-8");
response.setContentType("application/vnd.ms-excel;charset=UTF-8");
response.setHeader("Content-Disposition", "attachment;filename=" + fileName + ".xls");
OutputStream os = response.getOutputStream();
wb.write(os);
os.flush();
os.close();
} catch (Exception e) {
e.printStackTrace();
}
}
@GetMapping("importExcel")
@ApiOperation(value = "导入Excel",notes = "将数据以Excel的形式导入到数据库中")
public Boolean importExcel(@RequestParam("file") MultipartFile file, HttpServletRequest request) throws Exception {
//获取用户上传表格的地址，执行完程序后表格将会删除，避免占用内存
String filePath = request.getSession().getServletContext().getRealPath("/");
//根据地址和文件名准确获取用户上传的表格
File tempFile = new File(filePath+file.getOriginalFilename());
try {
//将MultipartFile转换为File类型
file.transferTo(tempFile);
List> dataList = ExcelImport.read(tempFile,5);
User user = new User();
for (int i = 0; i < dataList.size(); i++) {
//此处的取值顺序取决于Excel表的表头顺序，一一对应
//学生id 姓名 性别 年龄 学校
user.setUserId(Integer.valueOf(dataList.get(i).get(0)));
user.setUserName(dataList.get(i).get(1));
user.setSex(dataList.get(i).get(2));
user.setAge(Integer.valueOf(dataList.get(i).get(3)));
user.setSchool(dataList.get(i).get(4));
//此处应该将user对象插入数据库中
//UserService.insert(user);
}
//执行完程序后删除用户上传文件
tempFile.delete();
} catch (Exception e) {
tempFile.delete();
throw new Exception("批量录入用户失败，请检查表格中的数据是否和数据库中的数据冲突！");
}
return true;
}
}
3、相关jar包
org.apache.poi
poi
3.7
org.apache.poi
poi-ooxml
3.7
org.apache.poi
poi-ooxml-schemas
3.7
最后附上我的小demo项目地址：https://github.com/djw2014/ExcelUtils