介绍

EasyExcel是阿里巴巴出品的Excel文件处理工具，功能十分强大，能省去我们很多的编码，下面来通过一个例子，看看如何使用EasyExcel导出Excel文件的

准备

我们从数据库读取User实体对象数据，然后使用EasyExcel写入到HttpServletResponse输出流中，在浏览器就可以下载导出的Excel文件了

POM

主要有EasyExcel依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://maven.apache.org/POM/4.0.0"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.1</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>excel</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>excel</name>
    <description>excel</description>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.2.2</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</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>

        <!--excel-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>easyexcel</artifactId>
            <version>2.2.3</version>
        </dependency>

        <!--json-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.69</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>

</project>

User实体

@ExcelProperty(value = “id”) 表示导出的Excel文件列名为id，其他同理

package com.example.excel.entity;

import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.annotation.format.DateTimeFormat;
import lombok.Data;

import java.math.BigDecimal;
import java.util.Date;

@Data
public class User {

    @ExcelProperty("id")
    private String id;

    @ExcelProperty("username")
    private String username;

    @ExcelProperty("password")
    private String password;

    @ExcelProperty("address")
    private String address;

    @ExcelProperty("email")
    private String email;

    @ExcelProperty("profile")
    private String profile;

    @ExcelProperty("birthday")
    @DateTimeFormat("yyyy-MM-dd")
    private Date birthday;

    @ExcelProperty("registerDay")
    @DateTimeFormat("yyyy-MM-dd")
    private Date registerDay;

    @ExcelProperty("loginDay")
    @DateTimeFormat("yyyy-MM-dd")
    private Date loginDay;

    @ExcelProperty("status")
    private Integer status;

    @ExcelProperty("account")
    private BigDecimal account;

    @ExcelProperty("balance")
    private BigDecimal balance;

    @ExcelProperty("age")
    private Integer age;

    @ExcelProperty("sex")
    private Integer sex;

    @ExcelProperty("avatar")
    private String avatar;

    @ExcelProperty("level")
    private Integer level;

}

ExcelUtil

实现浏览器导出下载Excel文件，写入本地文件也类似，可参考：EasyExcel使用

package com.example.excel.util;

import com.alibaba.excel.EasyExcel;

import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.net.URLEncoder;
import java.util.List;

/**
 * @description: ExcelUtil
 * @author: zj
 * @date: 2022-07-14 17:07
 */
public class ExcelUtil {

    public static void exportExcel(List<?> objects, Class clazz, String fileName,
                                   String sheetName, HttpServletResponse response) throws IOException {

        // 设置响应头
        response.setContentType("application/vnd.ms-excel");
        response.setCharacterEncoding("utf-8");

        // 设置防止中文名乱码
        String exportName = URLEncoder.encode(fileName, "utf-8");
        String sheetSubName = URLEncoder.encode(sheetName, "utf-8");

        // 文件下载方式(附件下载还是在当前浏览器打开)
        response.setHeader("Content-disposition", "attachment;filename=" +
                exportName + ".xlsx");

        // 向Excel中写入数据
        EasyExcel.write(response.getOutputStream(), clazz)
                .sheet(sheetSubName)
                .doWrite(objects);

    }

}

Controller

实现从MySQL读取数据，写入HttpServletResponse流中的主要逻辑

package com.example.excel.controller;

import com.example.excel.entity.User;
import com.example.excel.mapper.UserMapper;
import com.example.excel.util.ExcelUtil;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.List;

/**
 * @description: Excel
 * @author: zj
 * @date: 2022-07-14 17:02
 */
@RestController
@Slf4j
public class ExcelController {

    @Resource
    private UserMapper userMapper;


    @GetMapping("/excel")
    public void excel(HttpServletResponse response) throws IOException {

        long st = System.currentTimeMillis();

        List<User> users = userMapper.selectSub(0, 10000);

        ExcelUtil.exportExcel(users, User.class, "user_info", "sheet_one", response);

        log.info("export excel success, cost {} s.", (System.currentTimeMillis() - st) / 1000);

    }

}

效果

浏览器输入接口地址下载Excel文件

浏览器输入localhost/excel

导出文件

APIFox

注意：返回的是文件流

easyexcel 引入：

        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-collections4</artifactId>
            <version>4.4</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>easyexcel</artifactId>
            <version>2.2.3</version>
        </dependency>

MAIN：

import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.ExcelWriter;
import com.alibaba.excel.annotation.ExcelIgnore;
import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.annotation.format.DateTimeFormat;
import com.alibaba.excel.annotation.format.NumberFormat;
import com.alibaba.excel.write.metadata.WriteSheet;
import com.google.common.collect.Lists;
import java.math.BigDecimal;
import java.util.Date;
import java.util.List;
import lombok.Data;

/**
 * 类${file_name}的实现描述：TODO 类实现描述
 *
 * @Author: za-qishaohui
 * @Date: 2021/11/22 15:40
 */
public class WriteTest {

  private static List<DemoData> data() {
    List<DemoData> list = Lists.newArrayList();
    for (int i = 0; i < 10; i++) {
      DemoData data = new DemoData();
      data.setString("字符串" + i);
      data.setDate(new Date());
      data.setDoubleData(0.5678);
      data.setNumData(new BigDecimal("56.01234"));
      list.add(data);
    }
    return list;
  }

  @Data
  public static class DemoData {

    @ExcelProperty("字符串标题")
    private String string;
    @ExcelProperty("日期标题")
    @DateTimeFormat("yyyy-MM-dd")
    private Date date;
    @ExcelProperty("数字标题1")
    @NumberFormat("#.##%")
    private Double doubleData;

    @ExcelProperty("数字标题2")
    @NumberFormat("#.##")
    private BigDecimal numData;
    /**
     * 忽略这个字段
     */
    @ExcelIgnore
    private String ignore;
  }

  /**
   * 最简单的写
   * <p>1. 创建excel对应的实体对象 参照{@link DemoData}
   * <p>2. 直接写即可
   */
  public static void main(String[] args) {
    // 写法1
    String fileName = TestFileUtil.getPath() + "simpleWrite" + System.currentTimeMillis() + ".xlsx";
    System.out.println(fileName);
    // 这里 需要指定写用哪个class去写，然后写到第一个sheet，名字为模板 然后文件流会自动关闭
    // 如果这里想使用03 则 传入excelType参数即可
    EasyExcel.write(fileName, DemoData.class).sheet("模板").doWrite(data());

    // 写法2
    fileName = TestFileUtil.getPath() + "simpleWrite" + System.currentTimeMillis() + ".xlsx";
    System.out.println(fileName);
    // 这里 需要指定写用哪个class去写
    ExcelWriter excelWriter = EasyExcel.write(fileName, DemoData.class).build();
    WriteSheet writeSheet = EasyExcel.writerSheet("模板").build();
    excelWriter.write(data(), writeSheet);
    // 千万别忘记finish 会帮忙关闭流
    excelWriter.finish();
  }
}

工具类：

import java.io.File;
import java.io.InputStream;

public class TestFileUtil {


    public static InputStream getResourcesFileInputStream(String fileName) {
        return Thread.currentThread().getContextClassLoader().getResourceAsStream("" + fileName);
    }

    public static String getPath() {
        return TestFileUtil.class.getResource("/").getPath();
    }

    public static File createNewFile(String pathName) {
        File file = new File(getPath() + pathName);
        if (file.exists()) {
            file.delete();
        } else {
            if (!file.getParentFile().exists()) {
                file.getParentFile().mkdirs();
            }
        }
        return file;
    }

    public static File readFile(String pathName) {
        return new File(getPath() + pathName);
    }

    public static File readUserHomeFile(String pathName) {
        return new File(System.getProperty("user.home") + File.separator + pathName);
    }
}

第一步：
导入依赖

    <!-- 导处Excel -->
    <dependency>
      <groupId>com.alibaba</groupId>
      <artifactId>easyexcel</artifactId>
      <version>3.0.0-beta3</version>
    </dependency>

第二步：
新建方法类

package com.lc.yangzi.module.marketing.sell;

import lombok.extern.slf4j.Slf4j;
import com.alibaba.excel.EasyExcel;
import com.alibaba.excel.support.ExcelTypeEnum;
import org.apache.poi.util.IOUtils;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.List;

/**
 * Excel工具类
 */
@Slf4j
public class ExcelUtils {

    /**
     * 导出Excel(07版.xlsx)到指定路径下
     *
     * @param path      路径
     * @param excelName Excel名称
     * @param sheetName sheet页名称
     * @param clazz     Excel要转换的类型
     * @param data      要导出的数据
     */
    public static void export2File(String path, String excelName, String sheetName, Class clazz, List data) {
        String fileName = path.concat(excelName).concat(ExcelTypeEnum.XLSX.getValue());
        EasyExcel.write(fileName, clazz).sheet(sheetName).doWrite(data);
    }

    /**
     * 导出Excel(07版.xlsx)到web
     *
     * @param response  响应
     * @param excelName Excel名称
     * @param sheetName sheet页名称
     * @param clazz     Excel要转换的类型
     * @param data      要导出的数据
     * @throws Exception
     */
    public static void export2Web(HttpServletResponse response, String excelName, String sheetName, Class clazz, List data) throws Exception {
        response.setContentType("application/vnd.ms-excel");
        response.setCharacterEncoding("utf-8");
        // 这里URLEncoder.encode可以防止中文乱码
        excelName = URLEncoder.encode(excelName, "UTF-8");
        response.setHeader("Content-disposition", "attachment;filename=" + excelName + ExcelTypeEnum.XLSX.getValue());
        EasyExcel.write(response.getOutputStream(), clazz).sheet(sheetName).doWrite(data);
    }

    /**
     * 将指定位置指定名称的Excel导出到web
     *
     * @param response  响应
     * @param path      文件路径
     * @param excelName 文件名称
     * @return
     * @throws UnsupportedEncodingException
     */
    public static String export2Web4File(HttpServletResponse response, String path, String excelName) throws UnsupportedEncodingException {
        File file = new File(path.concat(excelName).concat(ExcelTypeEnum.XLSX.getValue()));
        if (!file.exists()) {
            return "文件不存在！";
        }

        response.setContentType("application/vnd.ms-excel");
        response.setCharacterEncoding("utf-8");
        // 这里URLEncoder.encode可以防止中文乱码
        excelName = URLEncoder.encode(excelName, "UTF-8");
        response.setHeader("Content-disposition", "attachment;filename=" + excelName + ExcelTypeEnum.XLSX.getValue());

        try (
                FileInputStream in = new FileInputStream(file);
                ServletOutputStream out = response.getOutputStream();
        ) {
            IOUtils.copy(in, out);
            return "导出成功！";
        } catch (Exception e) {
            log.error("导出文件异常：", e);
        }

        return "导出失败！";
    }

}

第二步：
新建要导出的列表类

package com.lc.yangzi.module.marketing.sell.customerinfo.domain;

import com.alibaba.excel.annotation.ExcelIgnore;
import com.alibaba.excel.annotation.ExcelProperty;
import com.alibaba.excel.annotation.write.style.ColumnWidth;
import lombok.Data;

@Data
public class CustomerInfoExcel {

    @ColumnWidth(20) // 定义列宽
    @ExcelProperty(value = {"客户名称"}, index = 0)
    private String customerName;//客户名称
    @ColumnWidth(20) // 定义列宽
    @ExcelProperty(value = {"客户等级"}, index = 1)
    private Integer customerLevel;//客户等级：A，B，C，D
    @ColumnWidth(20) // 定义列宽
    @ExcelProperty(value = {"地址"}, index = 2)
    private String address;//地址
    @ColumnWidth(20) // 定义列宽
    @ExcelProperty(value = {"联系电话"}, index = 3)
    private String contactPhone;//联系电话
    @ColumnWidth(20) // 定义列宽
    @ExcelProperty(value = {"审核状态"}, index = 4)
    private String auditStatusName;//状态
    @ColumnWidth(20) // 定义列宽
    @ExcelProperty(value = {"提货状态"}, index = 5)
    private String pickingStatusName;//提货状态
    @ColumnWidth(20) // 定义列宽
    @ExcelProperty(value = {"管理人"}, index = 6)
    private String managerUserName;//管理人姓名(多个逗号分隔)


    @ExcelIgnore
    private Integer auditStatus;//审核状态审核状态：0草稿1审核中2已完结
    @ExcelIgnore
    private Long id;//主键ID
    @ExcelIgnore
    private Long orgId;//和组织管联 yz_sys_org where category = 3、
    @ExcelIgnore
    private Integer pickingStatus;//提货状态
    @ExcelIgnore
    private Long createUserId;//创建人
}

第四步：
调用方法

    //导出Excel
    @RequestMapping(value="/exportExcel", method = RequestMethod.GET)
    public void exportExcel(HttpServletRequest request, HttpServletResponse response) {
        try {
            String customerId = request.getParameter("customerId");
            String auditStatus = request.getParameter("auditStatus");
            String pickingStatus = request.getParameter("pickingStatus");

            if(StringUtils.isBlank(customerId)){
                customerId="0";
            }if(StringUtils.isBlank(auditStatus)){
                auditStatus="-1";
            }if(StringUtils.isBlank(pickingStatus)){
                pickingStatus="0";
            }
            List<CustomerInfoExcel> list = customerInfoService.selectAllCustomerInfoExcel(Long.parseLong(customerId),Integer.parseInt(auditStatus),Integer.parseInt(pickingStatus));
            ExcelUtils.export2Web(response, "客户信息", "客户信息", CustomerInfoExcel.class, list);
        } catch (Exception e) {
            log.error("报表导出异常:", e);
        }
    }