upload

S3上传创建临时文件，然后分片上传

String username = SecurityUtils.getUsername();
String regex = ".*[\\u4e00-\\u9fa5]+.*";
// 创建线程池，根据实际环境调整线程数
ExecutorService executor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
List<Future<?>> futures = new ArrayList<>();
InputStream inputStream = file.getInputStream();
try (ZipArchiveInputStream zipInputStream = new ZipArchiveInputStream(inputStream)) {
    ZipArchiveEntry entry;
    while ((entry = zipInputStream.getNextZipEntry()) != null) {
        if (!entry.isDirectory()) {
            String zipEntryName = entry.getName();
            if (zipEntryName.matches(regex)) {
                throw new Exception("压缩文件中不能包含中文名");
            }
            // 处理 key
            String key = StringUtils.isNotEmpty(folderName)
                ? folderName + "/" + zipEntryName.replaceAll(" ", "_")
                : zipEntryName.replaceAll(" ", "_");

            // 创建临时文件存放当前条目的数据（确保不占用大量内存）
            File tempFile = File.createTempFile("upload_", "_" + zipEntryName.replaceAll("[\\\\/]", "_"));
            try (OutputStream out = new FileOutputStream(tempFile)) {
                byte[] buffer = new byte[8192];
                int len;
                while ((len = zipInputStream.read(buffer)) != -1) {
                    out.write(buffer, 0, len);
                }
            }
            // 提交上传任务，每个任务从磁盘读取临时文件进行上传
            ZipArchiveEntry finalEntry = entry;
            futures.add(executor.submit(() -> {
                try (InputStream uploadStream = new FileInputStream(tempFile)) {
                    // 设置对象元数据
                    ObjectMetadata objectMetadata = new ObjectMetadata();       				                                                     objectMetadata.setContentType(getContentType(finalEntry.getName()));
                    objectMetadata.addUserMetadata("uploader", username);
                    objectMetadata.setContentLength(tempFile.length());
                    // 调用分片上传（建议内部采用 TransferManager 或 S3 异步 API）
                    initiateMultipartUpload2(key, uploadStream, objectMetadata);
                } catch (Exception e) {
                    //                            log.error("上传文件 {} 失败，原因：{}", key, e.getMessage(), e);
                    throw new RuntimeException("上传文件 " + key + " 失败", e);
                } finally {
                    // 上传完成后删除临时文件
                    if (!tempFile.delete()) {
                        // 如删除失败可记录日志
                        System.err.println("临时文件删除失败：" + tempFile.getAbsolutePath());
                    }
                }
            }));
        }
    }
} finally {
    inputStream.close();
}

// 等待所有上传任务完成
for (Future<?> future : futures) {
    future.get();  // 如果某个任务失败，这里会抛出异常
}
executor.shutdown();

分片上传实现

// 初始化分片上传
InitiateMultipartUploadRequest initRequest = new InitiateMultipartUploadRequest(bucketName, key, objectMetadata);
InitiateMultipartUploadResult initResponse = amazonS3.initiateMultipartUpload(initRequest);
String uploadId = initResponse.getUploadId();

// 分片上传设置
List<PartETag> partETags = new ArrayList<>();
int partSize = 5 * 1024 * 1024; // 每个分片 5MB
byte[] buffer = new byte[partSize];
int partNumber = 1;

while (true) {
    // 按分片大小读取数据
    int bytesReadTotal = 0;
    while (bytesReadTotal < partSize) {
        int bytesRead = inputStream.read(buffer, bytesReadTotal, partSize - bytesReadTotal);
        if (bytesRead == -1) {
            break;
        }
        bytesReadTotal += bytesRead;
    }
    if (bytesReadTotal == 0) {
        break; // 没有数据则退出循环
    }
    // 使用 ByteArrayInputStream 包装当前分片数据
    ByteArrayInputStream partStream = new ByteArrayInputStream(buffer, 0, bytesReadTotal);
    // 创建上传请求
    UploadPartRequest uploadRequest = new UploadPartRequest()
        .withBucketName(bucketName)
        .withKey(key)
        .withUploadId(uploadId)
        .withPartNumber(partNumber)
        .withPartSize(bytesReadTotal)
        .withInputStream(partStream);
    UploadPartResult uploadResult = amazonS3.uploadPart(uploadRequest);
    partETags.add(uploadResult.getPartETag());
    partNumber++;
    // 如果本次读取的数据小于分片大小，说明已到末尾，退出循环
    if (bytesReadTotal < partSize) {
        break;
    }
}

// 完成分片上传
CompleteMultipartUploadRequest completeRequest = new CompleteMultipartUploadRequest(
    bucketName, key, uploadId, partETags);
amazonS3.completeMultipartUpload(completeRequest);

下载文件并打成压缩包

folderPrefix = folderPrefix.trim().replace(" ", "_");
response.setContentType("application/zip");
response.setHeader("Content-Disposition", "attachment; filename=file.zip");

try (ZipOutputStream zipOutputStream = new ZipOutputStream(response.getOutputStream())) {
    ListObjectsV2Request listObjectsRequest = new ListObjectsV2Request()
        .withBucketName(bucketName)
        .withPrefix(folderPrefix + "/");

    String continuationToken = null;
    boolean moreFiles = true;
    while (moreFiles) {
        listObjectsRequest.setContinuationToken(continuationToken);
        ListObjectsV2Result result = amazonS3.listObjectsV2(listObjectsRequest);
        List<S3ObjectSummary> objectSummaries = result.getObjectSummaries();

        for (S3ObjectSummary summary : objectSummaries) {
            String key = summary.getKey();
            downloadFile(bucketName, key, zipOutputStream, folderPrefix);
        }

        continuationToken = result.getNextContinuationToken();
        moreFiles = continuationToken != null;
    }

    zipOutputStream.finish();
} catch (Exception e) {
    e.printStackTrace();
    response.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
}

下载方法

try (S3Object s3Object = amazonS3.getObject(bucketName, key);
     InputStream inputStream = s3Object.getObjectContent()) {

    // 创建一个新的 ZIP 条目
    ZipEntry zipEntry = new ZipEntry(key.substring(folderPrefix.length() + 1));
    zipOutputStream.putNextEntry(zipEntry);

    byte[] buffer = new byte[4096];
    int length;
    while ((length = inputStream.read(buffer)) > 0) {
        zipOutputStream.write(buffer, 0, length);
    }
    zipOutputStream.closeEntry(); // 关闭当前的 ZIP 条目
} catch (IOException e) {
    e.printStackTrace();
}