今天做需求突然看到之前产品提的需求，导出多个文件为压缩包。功能部分早就已经完成了，想到还没有过类似的记录，今天就记录下来吧，是记录也是学历，如果有不对的地方还请多多指教。以下贴出的代码是下载压缩包的源代码，我的文件资源是存储在服务器根目录下，表中记录的文件存储的绝对路径，通过路径反查获取资源下载，看官可根据自己项目的情况判断是否适用你当下的需求场景。废话不多说，直接上代码：
controller层：

/**
     * 下载压缩包
     * @param request
     * @param response
     * @param idDTO 传入文件id
     */
    @SneakyThrows
    @PostMapping("/download-zip")
    @ApiOperation(value = "下载文件为压缩包")
    public SwaggerAjaxResult downloadFileZip(HttpServletRequest request, HttpServletResponse response, @RequestBody @Valid UpdateFileDTO idDTO){
        return SwaggerAjaxResult.success(inspectionProblemService.downloadFileZip(request,response,idDTO.getId()));
    }

service 层代码：

/**
     * 下载文件为压缩包
     *
     * @param request
     * @param response
     * @param id
     */
    @Override
    @Transactional(rollbackFor = Exception.class)
    public SwaggerAjaxResult downloadFileZip(HttpServletRequest request, HttpServletResponse response, String id) {
        try {
            List<TFile> fileVOList = fileService.lambdaQuery()
                    .eq(TFile::getParentId, id)
                    .eq(TFile::getParentTable, PROBLEM_TABLE_NAME)
                    .eq(TFile::getType, WJXX)
                    .list();
            Assert.notNull(fileVOList, "文件为空!");

            String fileName = super.baseMapper.getFileName(id);
            Assert.notNull(fileName, "文件名不能为空!");
            //创建临时路径，存放压缩文件
            String zipFilePath = System.getProperty("user.dir") + File.separator + "downloadZip" + File.separator;
            log.info("文件临时路径为:{}", zipFilePath);
            //如果文件不存在创创建新文件
            File zipFile = new File(zipFilePath);
            if (!zipFile.exists()) {
                zipFile.mkdirs();
            }
            //在临时文件夹里创建临时文件
            String temporaryZipName = zipFilePath + "临时存放.zip";
            //如果不存在就新创建一个
            File zipFiles = new File(temporaryZipName);
            if (!zipFiles.exists()) {
                zipFiles.createNewFile();
            }

            //压缩输出流，将临时文件输出流包装成压缩流,将所有文件输出到这里,打成zip包
            ZipOutputStream zipOut = new ZipOutputStream(new FileOutputStream(temporaryZipName));
            //将文件写入压缩包
            for (TFile file : fileVOList) {
                writingFilesToZip(zipFilePath, zipOut, file, request);
            }
            //压缩完成关闭压缩流
            zipOut.close();
            response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "utf-8") + ".zip");
            response.setCharacterEncoding("UTF-8");
            response.setHeader("Access-Control-Expose-Headers", "Content-Disposition");
            ServletOutputStream outputStream = response.getOutputStream();
            FileInputStream inputStream = new FileInputStream(temporaryZipName);
            IOUtils.copy(inputStream, outputStream);
            //关闭输入流
            inputStream.close();
            //下载完成，删除临时文件
            File file = new File(zipFilePath);

            FileUtils.deleteFile(file);
            log.info("下载zip成功！");
            return SwaggerAjaxResult.success("下载zip成功！");
        } catch (IOException e) {
            e.printStackTrace();
            log.warn("下载zip失败!{}", e.getMessage());
            return SwaggerAjaxResult.error("下载zip失败!{}", e.getMessage());
        }
    }

/**
     * @param zipFilePath
     * @param zipOut
     * @param fileVO
     */
    private void writingFilesToZip(String zipFilePath, ZipOutputStream zipOut, TFile fileVO, HttpServletRequest request) throws IOException {
        String savePath = fileVO.getFileLink();
        //通过URL将文件下载至本地
        downLoadFromUrl(savePath, zipFilePath, fileVO.getFileName(), request);
        byte[] buf = new byte[2 * 1024];
        String srcDir = zipFilePath + fileVO.getFileName();
        File sourceFile = new File(srcDir);
        zipOut.putNextEntry(new ZipEntry(fileVO.getFileName()));
        int len;
        FileInputStream in = new FileInputStream(sourceFile);
        while ((len = in.read(buf)) != -1) {
            zipOut.write(buf, 0, len);
        }
        zipOut.closeEntry();
        in.close();

    }

private void downLoadFromUrl(String savePath, String zipFilePath, String fileName, HttpServletRequest request) throws IOException {
        File file1 = new File(savePath);
        byte[] getData = new byte[0];
        try {
            getData = org.apache.commons.io.FileUtils.readFileToByteArray(file1);
        } catch (IOException e) {
            log.warn("文件:{}不能访问!", savePath);
        }
        //文件保存位置
        File saveDir = new File(zipFilePath);
        if (!saveDir.exists()) {
            saveDir.mkdir();
        }

        File file = new File(saveDir + File.separator + fileName);
        FileOutputStream fos = new FileOutputStream(file);
        fos.write(getData);
        fos.close();
    }

– 2024-02-22更新
用java包里面的方法导出压缩包

//导出压缩包文件名称
response.setHeader("Content-disposition", "attachment;filename="
                    + DateUtil.parseDate(reqParam.getStartTime()).toString(DatePattern.PURE_DATE_PATTERN) + "-"
                    + DateUtil.parseDate(reqParam.getEndTime()).toString(DatePattern.PURE_DATE_PATTERN)
                    + URLEncoder.encode("xxxx管理信息", "UTF-8") + ".zip");
            ZipOutputStream zipOutputStream = new ZipOutputStream(outputStream);
            //groupByDate为将要导出的文件数据，我这里是按照数据的日期分组了，按日期数据为一个excel导出，最后组成一个压缩包
            try {
                for (Map.Entry<String, List<GrainReserveInfoVO>> entry : groupByDate.entrySet()) {
                    String key = entry.getKey();
                    AtomicInteger serialNo = new AtomicInteger(1);
                    entry.getValue().forEach(temp -> temp.setSerialNo(serialNo.getAndIncrement()));
                    ExcelWriter excelWriter = EasyExcel.write()
                            .excelType(ExcelTypeEnum.XLSX)
                            .autoCloseStream(Boolean.FALSE)
                            .registerWriteHandler(new HorizontalCellStyleStrategy(headStyle, bodyStyle))
                            .build();
                    WriteSheet writeSheet = EasyExcel.writerSheet(key.substring(5, 7) + "月" + key.substring(8) + "日").build();
                    WriteTable writeTable = EasyExcel.writerTable(0).head(GrainReserveInfoVO.class).needHead(Boolean.TRUE).build();
                    excelWriter.write(entry.getValue(), writeSheet, writeTable);
                    //压缩包里每一个文件名称设置
                    ZipEntry zipEntry = new ZipEntry(DateUtil.parseDate(key).toString(DatePattern.PURE_DATE_PATTERN) + "xxxx管理信息.xlsx");
                    zipOutputStream.putNextEntry(zipEntry);
                    Workbook workbook = excelWriter.writeContext().writeWorkbookHolder().getWorkbook();
                    workbook.write(zipOutputStream);
                }
                zipOutputStream.flush();
            } catch (Exception e) {
                log.error("导出xxxx失败", e);
                throw new CustomException("导出xxxx异常");
            } finally {
                //关闭数据流，注意关闭的顺序
                zipOutputStream.close();
                outputStream.close();
            }

如有不足，请多多指教！