前言

之前写过一篇极其简单的excel导入导出，是单个文件的：
Springboot 最简单的结合MYSQL数据实现EXCEL表格导出及数据导入_小目标青年的博客-CSDN博客

还有指定模板的：

Springboot 指定自定义模板导出Excel文件_小目标青年的博客-CSDN博客

今天有人问到，多个文件导出，放到zip压缩包里面怎么搞？

不多说，开搞。

正文

三步：

引入核心依赖
复制粘贴已经给你们写好的工具类
送一步，自测看效果

第一步，引依赖

<!-- 导入和导出-->
<dependency>
    <groupId>cn.afterturn</groupId>
    <artifactId>easypoi-base</artifactId>
    <version>3.0.3</version>
</dependency>
<dependency>
    <groupId>cn.afterturn</groupId>
    <artifactId>easypoi-web</artifactId>
    <version>3.0.3</version>
</dependency>
<dependency>
    <groupId>cn.afterturn</groupId>
    <artifactId>easypoi-annotation</artifactId>
    <version>3.0.3</version>
</dependency>

第二步，加工具类

ExcelUtil.java

import cn.afterturn.easypoi.excel.ExcelExportUtil;
import cn.afterturn.easypoi.excel.entity.ExportParams;
import org.apache.poi.ss.usermodel.Workbook;
import javax.servlet.http.HttpServletResponse;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.net.URLEncoder;
import java.util.List;

/**
 * @Author: JCccc
 * @Date: 2022-7-13 16:02
 * @Description: excel工具类
 */
public class ExcelUtil {

    /**
     * 导出
     * @param list
     * @param title
     * @param sheetName
     * @param pojoClass
     * @param fileName
     * @param response
     */
    public static void exportExcel(List<?> list, String title, String sheetName, Class<?> pojoClass, String fileName, HttpServletResponse response) {
        defaultExport(list, pojoClass, fileName, response, new ExportParams(title, sheetName));
    }

    /**
     * 导出excle转换成 bytes
     * @param list
     * @param title
     * @param sheetName
     * @param pojoClass
     * @param fileName
     * @param response
     * @return
     * @throws IOException
     */
    public static byte[] getExportExcelBytes(List<?> list, String title, String sheetName, Class<?> pojoClass, String fileName, HttpServletResponse response) throws IOException {
        Workbook workbook = ExcelExportUtil.exportExcel(new ExportParams(title, sheetName), pojoClass, list);
        ByteArrayOutputStream os = new ByteArrayOutputStream();
        workbook.write(os);
        return os.toByteArray();
    }

    private static void defaultExport(List<?> list, Class<?> pojoClass, String fileName, HttpServletResponse response, ExportParams exportParams) {
        Workbook workbook = ExcelExportUtil.exportExcel(exportParams, pojoClass, list);
        downLoadExcel(fileName, response, workbook);
    }
    private static void downLoadExcel(String fileName, HttpServletResponse response, Workbook workbook) {
        try {
            response.setCharacterEncoding("UTF-8");
            response.setHeader("content-Type", "application/vnd.ms-excel");
            response.setHeader("Content-Disposition",
                    "attachment;filename=" + URLEncoder.encode(fileName, "UTF-8"));
            workbook.write(response.getOutputStream());
        } catch (IOException e) {
            throw new RuntimeException(e.getMessage());
        }
    }

}

ZipUtils.java

import java.io.*;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.zip.ZipEntry;
import java.util.zip.ZipOutputStream;
import static org.springframework.util.StreamUtils.BUFFER_SIZE;

/**
 * @Author: JCccc
 * @Date: 2022-7-13 16:02
 * @Description: zip工具类
 */
public class ZipUtils {

    /**
     * 传入文件file
     * @param outputStream
     * @param fileList
     */
    public static void downloadZipForFiles(OutputStream outputStream, List<File> fileList){

        ZipOutputStream zipOutputStream = null;
        try {
            zipOutputStream = new ZipOutputStream(outputStream);
            for (File file : fileList) {
                ZipEntry zipEntry = new ZipEntry(file.getName());
                zipOutputStream.putNextEntry(zipEntry);
                byte[] buf = new byte[BUFFER_SIZE];
                int len;
                FileInputStream in = new FileInputStream(file);
                while ((len = in.read(buf)) != -1) {
                    zipOutputStream.write(buf, 0, len);
                    zipOutputStream.flush();
                }
            }
            zipOutputStream.flush();
            zipOutputStream.close();

        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭流
            try {
                if (zipOutputStream != null ) {
                    zipOutputStream.close();
                }
                if (outputStream != null) {
                    outputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

    }

    /**
     * 传入文件的 byte[]
     * Map<String,byte[]> fileBufMap key是文件名（包含后缀），value是文件的byte[]
     * @param outputStream
     * @param fileBufMap
     */
    public static void downloadZipForByteMore(OutputStream outputStream,Map<String,byte[]> fileBufMap)  {

            ZipOutputStream zipOutputStream = null;
            try {
                zipOutputStream = new ZipOutputStream(outputStream);
                for (String fileName:fileBufMap.keySet()){
                    ZipEntry zipEntry = new ZipEntry(fileName);
                    zipOutputStream.putNextEntry(zipEntry);
                    if (Objects.nonNull(fileBufMap.get(fileName))){
                        byte[] fileBytes = fileBufMap.get(fileName);
                        zipOutputStream.write(fileBytes);
                        zipOutputStream.flush();
                    }
                }
                zipOutputStream.flush();
                zipOutputStream.close();

            } catch (IOException e) {
                e.printStackTrace();
            }finally {
                // 关闭流
                try {
                    if (zipOutputStream != null ) {
                        zipOutputStream.close();
                    }
                    if (outputStream != null) {
                        outputStream.close();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
    }

    /**
     * 返回zip包的 byte[]
     *
     * @param fileBufMap
     * @return
     */

    public static byte[] getZipForByteMore(Map<String,byte[]> fileBufMap)  {
        ByteArrayOutputStream totalZipBytes = null;
        ZipOutputStream zipOutputStream = null;
        try {
            totalZipBytes = new ByteArrayOutputStream();
            zipOutputStream = new ZipOutputStream(totalZipBytes);
            for (String fileName:fileBufMap.keySet()){
                ZipEntry zipEntry = new ZipEntry(fileName);
                zipOutputStream.putNextEntry(zipEntry);
                if (Objects.nonNull(fileBufMap.get(fileName))){
                    byte[] fileBytes = fileBufMap.get(fileName);
                    zipOutputStream.write(fileBytes);
                    zipOutputStream.flush();
                }
            }
            zipOutputStream.close();
            byte[] bytes = totalZipBytes.toByteArray();
            totalZipBytes.close();// 关闭流
            return bytes;
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            // 关闭流
            try {
                if (totalZipBytes != null) {
                    totalZipBytes.close();
                }
                if (zipOutputStream != null) {
                    zipOutputStream.close();
                }

            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return null;
    }

}

第三步，使用工具类，看看效果

回顾一下，单个excel导出，写过使用场景接口：

@RequestMapping("exportUserExcel")
    public void exportUserExcel(HttpServletResponse response){
       // List<User> userList = userService.queryUserInfo();
        List<User> userList=new ArrayList<>();
        User user1=new User(1,"a","12");
        User user2=new User(1,"b","12");
        User user3=new User(1,"c","12");
        userList.add(user1);
        userList.add(user2);
        userList.add(user3);
        //导出操作
        ExcelUtil.exportExcel(userList,"用户信息","sheet1",User.class,"users.xls",response);
    }

调用一下：

多个文件导出，zip方式下载：

① 已经知道存在的文件路径

接口使用代码：

/**
     * 将指定文件打包成zip并下载
     */
    @RequestMapping("exportExcelZipWithFile")
    public void exportExcelZipWithFile(HttpServletResponse response) throws IOException {
        // 这里还是和上面一样
        String[] filePath = new String[]{"D:\\ziptest\\11.xls", "D:\\ziptest\\22.xls"};
        List<File> fileList = new ArrayList<>();
        for (String s : filePath) {
            File file = new File(s);
            fileList.add(file);
        }
        response.setHeader("content-type", "application/octet-stream");
        response.setContentType("application/octet-stream");
        response.setHeader(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=configDetail.zip");
        ZipUtils.downloadZipForFiles(response.getOutputStream(), fileList);
    }

效果：

②直接生成excel，转换成byte再导出zip

/**
     * 将excel文件的Byte[]打包成zip并下载
     */
    @RequestMapping("exportExcelZipWithByte")
    public void exportExcelZipWithByte(HttpServletResponse response) throws IOException {

        Map<String,byte[]> fileBufMap=new HashMap<>();

        List<Account> accountList=new ArrayList<>();
        Account account1=new Account(1,"1234");
        Account account2=new Account(2,"12222");
        Account account3=new Account(3,"1431546");
        accountList.add(account1);
        accountList.add(account2);
        accountList.add(account3);
        //导出操作 1
        byte[] exportAccountExcelBytes = ExcelUtil.getExportExcelBytes(accountList, "账号信息", "sheet1", Account.class, "accounts.xls", response);

        List<User> userList=new ArrayList<>();
        User user1=new User(1,"a","12");
        User user2=new User(1,"b","12");
        User user3=new User(1,"c","12");
        userList.add(user1);
        userList.add(user2);
        userList.add(user3);
        //导出操作
        byte[] exportUserExcelBytes =   ExcelUtil.getExportExcelBytes(userList,"用户信息","sheet1",User.class,"users.xls",response);

        fileBufMap.put("accounts.xls",exportAccountExcelBytes);
        fileBufMap.put("users.xls",exportUserExcelBytes);

        response.setHeader("content-type", "application/octet-stream");
        response.setContentType("application/octet-stream");
        response.setHeader(HttpHeaders.CONTENT_DISPOSITION, "attachment; filename=configDetail.zip");
        ZipUtils.downloadZipForByteMore(response.getOutputStream(), fileBufMap);
    }

代码简析：

这个map，key 是zip压缩包里面的文件名， vlaue是 excel文件的字节流：