Java 下载多个文件至内存并压缩文件包返回，无需保存至本地打包压缩

ゝ一纸荒年。 2024-03-31 12:36 21阅读 0赞

## 场景 ##

从其他服务器下载文件，将这些文件打包压缩后返回给浏览器。不想将文件下载到本地后在打包压缩，所以使用内存流

## 方案 ##

/** 入参：urlList -- 多个文件下载地址 ; filename -- 压缩包名称.zip */
    
    // 压缩包内文件夹名称
    String folderName = FilenameUtils.getBaseName(filename);
    // 下载并压缩
    try (ByteArrayOutputStream bos = new ByteArrayOutputStream();
        ZipOutputStream zos = new ZipOutputStream(bos)) {
        
      for (String url : urlList) {
        
        ZipEntry zipEntry = new ZipEntry(folderName + "/" + FilenameUtils.getName(url));
        zos.putNextEntry(zipEntry);
        try {
        
          Request request = OkHttpClientUtil.requestBuilder(url).get().build();
          Response response = OkHttpClientUtil.send(request);
          ResponseBody body = response.body();
          IOUtils.copy(body.byteStream(), zos);
          zos.flush();
          zos.closeEntry();
        } catch (IOException e) {
        
          throw new FileException("文件下载失败", e, ServiceResponseStatus.RUNTIME_ERROR);
        }
      }
      zos.finish();
      httpServletResponse.addHeader(
          "content-disposition",
          "attachment;filename=" + new String(filename.getBytes(), StandardCharsets.ISO_8859_1));
      OutputStream os = httpServletResponse.getOutputStream();
      IOUtils.copy(new ByteArrayInputStream(bos.toByteArray()), os);
      os.close();
    } catch (IOException e) {
        
      throw new FileException("xx文件压缩失败", e, ServiceResponseStatus.RUNTIME_ERROR);
    }