Java 使用OSS 文件分片上传MultipartFile

Java使用OSS文件分片上传MultipartFile的过程如下：
1. 首先需要将MultipartFile转换为文件分片，可以使用引用中提到的Base64ToMultipartFile工具类将base64字符串转换为MultipartFile。
2. 然后需要组装文件路径和分片路径，并将文件数据写入到分片路径中，可以使用引用中提到的代码实现。
3. 将所有分片上传到OSS服务器，并记录每个分片的上传结果和上传顺序。
4. 如果所有分片上传成功，则将所有分片合并成完整的文件，上传到OSS服务器。
5. 如果上传失败，则需要进行重试或者回滚操作。

相关问题

Java 使用OSS 文件分片上传MultipartFile代码

Java 使用OSS 文件分片上传MultipartFile代码可以分为以下几个步骤：
1. 引入OSS SDK依赖。
2. 初始化OSSClient对象。
3. 设置分片大小和并发数。
4. 创建InitiateMultipartUploadRequest对象并调用initiateMultipartUpload方法初始化分片上传任务。
5. 循环上传分片，创建UploadPartRequest对象并调用uploadPart方法上传分片。
6. 创建CompleteMultipartUploadRequest对象并调用completeMultipartUpload方法完成分片上传任务。

下面是Java使用OSS文件分片上传MultipartFile的代码示例：

// 引入OSS SDK依赖
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.model.*;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class OSSFileUploadUtil {

    // 初始化OSSClient对象
    private static final String endpoint = "yourEndpoint";
    private static final String accessKeyId = "yourAccessKeyId";
    private static final String accessKeySecret = "yourAccessKeySecret";
    private static final String bucketName = "yourBucketName";
    private static final OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);

    // 设置分片大小和并发数
    private static final int partSize = 1024 * 1024 * 1; // 1MB
    private static final int taskNum = 5;

    public static void uploadFileByMultipartFile(String localFilePath, String ossFilePath) throws IOException {
        // 创建InitiateMultipartUploadRequest对象并调用initiateMultipartUpload方法初始化分片上传任务
        InitiateMultipartUploadRequest request = new InitiateMultipartUploadRequest(bucketName, ossFilePath);
        InitiateMultipartUploadResult result = ossClient.initiateMultipartUpload(request);
        String uploadId = result.getUploadId();

        // 循环上传分片
        File file = new File(localFilePath);
        long fileLength = file.length();
        long partCount = fileLength / partSize + 1;
        if (fileLength % partSize == 0) {
            partCount--;
        }
        List<PartETag> partETags = new ArrayList<>();
        for (int i = 0; i < partCount; i++) {
            long startPos = i * partSize;
            long curPartSize = (i + 1 == partCount) ? (fileLength - startPos) : partSize;
            UploadPartRequest uploadPartRequest = new UploadPartRequest();
            uploadPartRequest.setBucketName(bucketName);
            uploadPartRequest.setKey(ossFilePath);
            uploadPartRequest.setUploadId(uploadId);
            uploadPartRequest.setPartNumber(i + 1);
            uploadPartRequest.setInputStream(FileUtil.getInputStreamByFile(file, startPos, curPartSize));
            uploadPartRequest.setPartSize(curPartSize);
            UploadPartResult uploadPartResult = ossClient.uploadPart(uploadPartRequest);
            partETags.add(uploadPartResult.getPartETag());
        }

        // 创建CompleteMultipartUploadRequest对象并调用completeMultipartUpload方法完成分片上传任务
        CompleteMultipartUploadRequest completeMultipartUploadRequest = new CompleteMultipartUploadRequest(bucketName, ossFilePath, uploadId, partETags);
        ossClient.completeMultipartUpload(completeMultipartUploadRequest);
    }
}

Java oss分片上传 返回文件链接

在Java中进行OSS分片上传，可以通过以下步骤返回文件链接：

1. 创建OSSClient对象，连接到OSS服务。例如：

   String endpoint = "<yourEndpoint>";
   String accessKeyId = "<yourAccessKeyId>";
   String accessKeySecret = "<yourAccessKeySecret>";
   String bucketName = "<yourBucketName>";
   
   OSSClient ossClient = new OSSClient(endpoint, accessKeyId, accessKeySecret);

2. 初始化分片上传，并获取UploadId。例如：

   InitiateMultipartUploadRequest request = new InitiateMultipartUploadRequest(bucketName, key);
   InitiateMultipartUploadResult result = ossClient.initiateMultipartUpload(request);
   String uploadId = result.getUploadId();

3. 上传分片。可以使用UploadPartRequest对象上传每个分片，并记录每个分片的ETag和PartNumber。例如：

    FileInputStream inputStream = new FileInputStream(file);
    long partSize = 5 * 1024 * 1024L;
    long fileLength = file.length();
    int partCount = (int) (fileLength / partSize);
    if (fileLength % partSize != 0) {
        partCount++;
    }
    List<PartETag> partETags = new ArrayList<PartETag>();
    for (int i = 0; i < partCount; i++) {
        long startPos = i * partSize;
        long curPartSize = (i + 1 == partCount) ? fileLength - startPos : partSize;
        inputStream.skip(startPos);
        UploadPartRequest uploadPartRequest = new UploadPartRequest();
        uploadPartRequest.setBucketName(bucketName);
        uploadPartRequest.setKey(key);
        uploadPartRequest.setUploadId(uploadId);
        uploadPartRequest.setInputStream(inputStream);
        uploadPartRequest.setPartSize(curPartSize);
        uploadPartRequest.setPartNumber(i + 1);
        UploadPartResult uploadPartResult = ossClient.uploadPart(uploadPartRequest);
        partETags.add(uploadPartResult.getPartETag());
    }

4. 完成分片上传。可以使用CompleteMultipartUploadRequest对象完成分片上传，并获取文件链接。例如：

   CompleteMultipartUploadRequest completeRequest = new CompleteMultipartUploadRequest(bucketName, key, uploadId, partETags);
   CompleteMultipartUploadResult completeResult = ossClient.completeMultipartUpload(completeRequest);
   String fileUrl = completeResult.getLocation();

fileUrl即为上传文件的链接。