当前位置：首页 > article >正文

在Spring Boot项目中导出复杂对象到Excel文件

article 2025/3/6 14:17:59

在Spring Boot项目中导出复杂对象到Excel文件，可以利用Hutool或EasyExcel等库来简化操作。这里我们将详细介绍如何使用Hutool和EasyExcel两种方式来实现这一功能。

使用Hutool导出复杂对象到Excel

首先确保你的pom.xml中添加了Hutool的依赖：

<dependency>
    <groupId>cn.hutool</groupId>
    <artifactId>hutool-all</artifactId>
    <version>5.8.10</version> <!-- 请根据实际情况选择最新版本 -->
</dependency>

接下来是一个简单的示例，展示如何导出一个包含复杂对象的列表到Excel文件。

示例代码

假设我们有一个User类，它包含一个嵌套的Address对象。

import cn.hutool.poi.excel.ExcelUtil;
import cn.hutool.poi.excel.ExcelWriter;

import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.net.URLEncoder;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.stream.Collectors;

@RestController
@RequestMapping("/api")
public class UserController {

    @GetMapping("/exportUsers")
    public void exportUsers(HttpServletResponse response) throws IOException {
        // 模拟获取用户数据
        List<User> users = getUsers();

        // 创建ExcelWriter实例
        ExcelWriter writer = ExcelUtil.getWriter(true); // true表示自动创建表头

        // 将复杂对象转换为Map列表，方便写入Excel
        List<Map<String, Object>> dataList = users.stream().map(user -> {
            Map<String, Object> row = new HashMap<>();
            row.put("ID", user.getId());
            row.put("姓名", user.getName());
            row.put("邮箱", user.getEmail());
            row.put("年龄", user.getAge());
            row.put("城市", user.getAddress().getCity());
            row.put("街道", user.getAddress().getStreet());
            return row;
        }).collect(Collectors.toList());

        // 写入数据
        writer.write(dataList, true);

        // 设置响应内容类型和头部信息
        response.setContentType("application/vnd.ms-excel;charset=utf-8");
        String fileName = URLEncoder.encode("用户列表", "UTF-8");
        response.setHeader("Content-Disposition", "attachment;filename=" + fileName + ".xlsx");

        // 将输出流写入response
        ServletOutputStream out = response.getOutputStream();
        writer.flush(out, true);
        out.close();
        writer.close();
    }

    private List<User> getUsers() {
        List<User> users = new ArrayList<>();
        Address address = new Address("北京", "中关村大街");
        users.add(new User(1L, "张三", "zhangsan@example.com", 28, address));
        return users;
    }
}

class User {
    private Long id;
    private String name;
    private String email;
    private Integer age;
    private Address address;

    public User(Long id, String name, String email, Integer age, Address address) {
        this.id = id;
        this.name = name;
        this.email = email;
        this.age = age;
        this.address = address;
    }

    // getter和setter方法
}

class Address {
    private String city;
    private String street;

    public Address(String city, String street) {
        this.city = city;
        this.street = street;
    }

    // getter和setter方法
}

使用EasyExcel导出复杂对象到Excel

EasyExcel是阿里巴巴开源的一个非常高效的Excel处理库，特别适合处理大数据量的Excel文件。首先，在pom.xml中添加EasyExcel的依赖：

<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>easyexcel</artifactId>
    <version>2.2.10</version> <!-- 请根据实际情况选择最新版本 -->
</dependency>

接下来是一个使用EasyExcel导出复杂对象的例子。

示例代码

假设我们仍然使用上面提到的User和Address类。

import com.alibaba.excel.EasyExcel;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

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

@RestController
@RequestMapping("/api")
public class EasyExcelController {

    @GetMapping("/exportUsers")
    public void exportUsers(HttpServletResponse response) throws IOException {
        // 模拟获取用户数据
        List<User> users = getUsers();

        // 设置响应内容类型和头部信息
        response.setContentType("application/vnd.ms-excel;charset=utf-8");
        String fileName = URLEncoder.encode("用户列表", "UTF-8");
        response.setHeader("Content-Disposition", "attachment;filename=" + fileName + ".xlsx");

        // 使用EasyExcel写出数据到输出流
        EasyExcel.write(response.getOutputStream(), UserData.class)
                .sheet("用户信息")
                .doWrite(users);
    }

    private List<User> getUsers() {
        List<User> users = new ArrayList<>();
        Address address = new Address("北京", "中关村大街");
        users.add(new User(1L, "张三", "zhangsan@example.com", 28, address));
        return users;
    }
}

// 数据实体类
class UserData {
    @com.alibaba.excel.annotation.ExcelProperty("ID")
    private Long id;

    @com.alibaba.excel.annotation.ExcelProperty("姓名")
    private String name;

    @com.alibaba.excel.annotation.ExcelProperty("邮箱")
    private String email;

    @com.alibaba.excel.annotation.ExcelProperty("年龄")
    private Integer age;

    @com.alibaba.excel.annotation.ExcelProperty("城市")
    private String city;

    @com.alibaba.excel.annotation.ExcelProperty("街道")
    private String street;

    // 构造函数、getter和setter方法
    public UserData(User user) {
        this.id = user.getId();
        this.name = user.getName();
        this.email = user.getEmail();
        this.age = user.getAge();
        this.city = user.getAddress().getCity();
        this.street = user.getAddress().getStreet();
    }

    // getter和setter方法
}