阿里云OSS对象存储

以下内容包含阿里云oss基本文件上传、下载操作操作，本质上是新建客户端、配置相关参数、调用相应接口，实现方式上大同小异，更多进阶操作参考官方文档即可：help.aliyun.com/zh/oss/?spm…

另外，我读取配置文件采取了编写代码方式读取，更优雅的读取配置方式参考：juejin.cn/post/707781…

开通对象存储OSS

创建Bucket

为了便于操作，这里修改一下相关的访问权限

创建目录

获取各种配置

Endpoint

ACCESS_KEY_ID和ACCESS_KEY_SECRET

创建用户

一定要保存好相关的AK、AKS

建立好用户后给用户设置权限(本人给了该用户：管理对象存储服务(OSS)权限、只读访问对象存储服务(OSS)权限、管理智能对话分析服务(SCA)的权限、只读访问智能对话分析服务(SCA)的权限)，如果后期需要云服务、云数据、CDN等权限自行新增授权即可

实操（快速开始）

配置文件

依赖

编写代码

package com.example.lzxoss;

import java.io.*;
import java.util.Properties;
import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import com.aliyun.oss.common.auth.DefaultCredentialProvider;
import com.aliyun.oss.model.OSSObject;
import com.aliyun.oss.model.ObjectListing;
import com.aliyun.oss.model.OSSObjectSummary;

public class OssJavaSdkQuickStart {
    public static void main(String[] args) throws IOException {
        String region = "cn-shenzhen";
        String endpoint;
        String bucketName;
        String AccessKey;
        String AccessKeySecret;
        String Folder;
        
        
        // 加载配置文件
        Properties prop = new Properties();
        try (InputStream input = OssJavaSdkQuickStart.class.getClassLoader().getResourceAsStream("aliyunoss.properties")) {
            if (input == null) {
                System.out.println("无法找到 aliyunoss.properties 文件");
                return;
            }
            prop.load(input);

            // 读取配置
            AccessKey = prop.getProperty("ACCESS_KEY_ID");
            AccessKeySecret = prop.getProperty("ACCESS_KEY_SECRET");
            endpoint = prop.getProperty("ENDPOINT");
            bucketName = prop.getProperty("BUCKET_NAME");
            Folder = prop.getProperty("FOLDER");
        }
        
        // 创建 OSSClient 实例
        DefaultCredentialProvider defaultCredentialProvider = new DefaultCredentialProvider(AccessKey, AccessKeySecret);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(defaultCredentialProvider)
                .region(region)
                .build();
                
        try {
            // 2. 上传文件
            String objectName = Folder + "helloOSS.txt";
            String content = "Hello OSS";
            ossClient.putObject(bucketName, objectName, new ByteArrayInputStream(content.getBytes()));
            System.out.println("2. 文件 " + objectName + " 上传成功。");
            
            // 3. 下载文件
            OSSObject ossObject = ossClient.getObject(bucketName, objectName);
            InputStream contentStream = ossObject.getObjectContent();
            BufferedReader reader = new BufferedReader(new InputStreamReader(contentStream));
            String line;
            System.out.println("3. 下载的文件内容：");
            while ((line = reader.readLine()) != null) {
                System.out.println(line);
            }
            contentStream.close();
            
            // 4. 列出文件
            System.out.println("4. 列出 Bucket 中的文件：");
            ObjectListing objectListing = ossClient.listObjects(bucketName);
            for (OSSObjectSummary objectSummary : objectListing.getObjectSummaries()) {
                System.out.println(" - " + objectSummary.getKey() + " (大小 = " + objectSummary.getSize() + ")");
            }
            
//            // 5. 删除文件
//            ossClient.deleteObject(bucketName, objectName);
//            System.out.println("5. 文件 " + objectName + " 删除成功。");
//            // 6. 删除存储空间（Bucket）
//            ossClient.deleteBucket(bucketName);
//            System.out.println("6. Bucket " + bucketName + " 删除成功。");
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException | IOException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

以上代码从开发文档中学习，其中删除Bucket需要保证Bucket中没有其他文件或目录，否则删除失败

效果

对象命名

注意：上传文件的保存路径必须用反斜线！！！！

文件上传

简单上传

注意事项

上手操作

package com.example.lzxoss;

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.model.PutObjectRequest;
import com.aliyun.oss.model.PutObjectResult;
import java.io.File;
import java.io.InputStream;
import java.util.Properties;

public class Demo {

    public static void main(String[] args) throws Exception {
        String endpoint;
        String bucketName;
        // 替换为您的 Bucket 区域
        String region = "cn-shenzhen";
        String AccessKey;
        String AccessKeySecret;
        String Folder;
        // 加载配置文件
        Properties prop = new Properties();
        try (InputStream input = OssJavaSdkQuickStart.class.getClassLoader().getResourceAsStream("aliyunoss.properties")) {
            if (input == null) {
                System.out.println("无法找到 aliyunoss.properties 文件");
                return;
            }
            prop.load(input);

            // 读取配置
            AccessKey = prop.getProperty("ACCESS_KEY_ID");
            AccessKeySecret = prop.getProperty("ACCESS_KEY_SECRET");
            endpoint = prop.getProperty("ENDPOINT");
            bucketName = prop.getProperty("BUCKET_NAME");
            Folder = prop.getProperty("FOLDER");

        }

        DefaultCredentialProvider defaultCredentialProvider = new DefaultCredentialProvider(AccessKey, AccessKeySecret);
        // 填写Object完整路径，完整路径中不能包含Bucket名称，例如exampledir/exampleobject.txt。
        String objectName = Folder + "示例pdf";
        // 填写本地文件的完整路径，例如D:\localpath\examplefile.txt。
        // 如果未指定本地路径，则默认从示例程序所属项目对应本地路径中上传文件。
        String filePath= "D:////edge默认下载位置//第五周作业.pdf";


        // 创建OSSClient实例。
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(defaultCredentialProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        try {
            // 创建PutObjectRequest对象。
            PutObjectRequest putObjectRequest = new PutObjectRequest(bucketName, objectName, new File(filePath));
            // 如果需要上传时设置存储类型和访问权限，请参考以下示例代码。
            // ObjectMetadata metadata = new ObjectMetadata();
            // metadata.setHeader(OSSHeaders.OSS_STORAGE_CLASS, StorageClass.Standard.toString());
            // metadata.setObjectAcl(CannedAccessControlList.Private);
            // putObjectRequest.setMetadata(metadata);

            // 上传文件。
            PutObjectResult result = ossClient.putObject(putObjectRequest);
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

分片上传

oss:PutObject的自定义权限配置如下

在OSS中，Resource支持使用通配符星号（*）来表示某类具体的资源。Resource的格式为acs:oss:{region}:{bucket_owner}:{bucket_name}/{object_name}。例如当Resource为acs:oss:*:*:mybucket/*，表示mybucket下的所有资源。当Resource为acs:oss:*:*:mybucket/abc*.txt，表示mybucket下前缀为abc且格式为.txt的所有文件。

将自定义的权限授权给用户

分片上传流程

注意事项

常见问题

上手操作

1、通过循环逐个分片上传

package com.example.lzxoss;

import com.aliyun.oss.*;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.internal.Mimetypes;
import com.aliyun.oss.model.*;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;

public class Demo1 {

    public static void main(String[] args) throws Exception {
        String endpoint;
        String bucketName;
        // 替换为您的 Bucket 区域
        String region = "cn-shenzhen";
        String AccessKey;
        String AccessKeySecret;
        String Folder;
        // 加载配置文件
        Properties prop = new Properties();
        try (InputStream input = OssJavaSdkQuickStart.class.getClassLoader().getResourceAsStream("aliyunoss.properties")) {
            if (input == null) {
                System.out.println("无法找到 aliyunoss.properties 文件");
                return;
            }
            prop.load(input);

            // 读取配置
            AccessKey = prop.getProperty("ACCESS_KEY_ID");
            AccessKeySecret = prop.getProperty("ACCESS_KEY_SECRET");
            endpoint = prop.getProperty("ENDPOINT");
            bucketName = prop.getProperty("BUCKET_NAME");
            Folder = prop.getProperty("FOLDER");

        }

        DefaultCredentialProvider defaultCredentialProvider = new DefaultCredentialProvider(AccessKey, AccessKeySecret);
        // 创建OSSClient实例。
        ClientBuilderConfiguration clientBuilderConfiguration = new ClientBuilderConfiguration();
        clientBuilderConfiguration.setSignatureVersion(SignVersion.V4);
        OSS ossClient = OSSClientBuilder.create()
                .endpoint(endpoint)
                .credentialsProvider(defaultCredentialProvider)
                .clientConfiguration(clientBuilderConfiguration)
                .region(region)
                .build();

        String objectName = Folder + "大文件.xmind";
        // 待上传本地文件路径。
        String filePath = "C:////Users//罗泽轩//Desktop//实习记录//ERP2.0学习记录.xmind";
        try {
            // 创建InitiateMultipartUploadRequest对象。
            InitiateMultipartUploadRequest request = new InitiateMultipartUploadRequest(bucketName, objectName);

            // 如果需要在初始化分片时设置请求头，请参考以下示例代码。
            ObjectMetadata metadata = new ObjectMetadata();
            // metadata.setHeader(OSSHeaders.OSS_STORAGE_CLASS, StorageClass.Standard.toString());
            // 指定该Object的网页缓存行为。
            // metadata.setCacheControl("no-cache");
            // 指定该Object被下载时的名称。
            // metadata.setContentDisposition("attachment;filename=oss_MultipartUpload.txt");
            // 指定该Object的内容编码格式。
            // metadata.setContentEncoding(OSSConstants.DEFAULT_CHARSET_NAME);
            // 指定初始化分片上传时是否覆盖同名Object。此处设置为true，表示禁止覆盖同名Object。
            // metadata.setHeader("x-oss-forbid-overwrite", "true");
            // 指定上传该Object的每个part时使用的服务器端加密方式。
            // metadata.setHeader(OSSHeaders.OSS_SERVER_SIDE_ENCRYPTION, ObjectMetadata.KMS_SERVER_SIDE_ENCRYPTION);
            // 指定Object的加密算法。如果未指定此选项，表明Object使用AES256加密算法。
            // metadata.setHeader(OSSHeaders.OSS_SERVER_SIDE_DATA_ENCRYPTION, ObjectMetadata.KMS_SERVER_SIDE_ENCRYPTION);
            // 指定KMS托管的用户主密钥。
            // metadata.setHeader(OSSHeaders.OSS_SERVER_SIDE_ENCRYPTION_KEY_ID, "9468da86-3509-4f8d-a61e-6eab1eac****");
            // 指定Object的存储类型。
            // metadata.setHeader(OSSHeaders.OSS_STORAGE_CLASS, StorageClass.Standard);
            // 指定Object的对象标签，可同时设置多个标签。
            // metadata.setHeader(OSSHeaders.OSS_TAGGING, "a:1");
            // request.setObjectMetadata(metadata);

            // 根据文件自动设置ContentType。如果不设置，ContentType默认值为application/oct-srream。
            if (metadata.getContentType() == null) {
                metadata.setContentType(Mimetypes.getInstance().getMimetype(new File(filePath), objectName));
            }

            // 初始化分片。
            InitiateMultipartUploadResult upresult = ossClient.initiateMultipartUpload(request);
            // 返回uploadId。
            String uploadId = upresult.getUploadId();
            // 根据uploadId执行取消分片上传事件或者列举已上传分片的操作。
            // 如果您需要根据uploadId执行取消分片上传事件的操作，您需要在调用InitiateMultipartUpload完成初始化分片之后获取uploadId。
            // 如果您需要根据uploadId执行列举已上传分片的操作，您需要在调用InitiateMultipartUpload完成初始化分片之后，且在调用CompleteMultipartUpload完成分片上传之前获取uploadId。
            // System.out.println(uploadId);

            // partETags是PartETag的集合。PartETag由分片的ETag和分片号组成。
            List<PartETag> partETags =  new ArrayList<PartETag>();
            // 每个分片的大小，用于计算文件有多少个分片。单位为字节。
            final long partSize = 1 * 1024 * 1024L;   //1 MB。

            // 根据上传的数据大小计算分片数。以本地文件为例，说明如何通过File.length()获取上传数据的大小。
            final File sampleFile = new File(filePath);
            long fileLength = sampleFile.length();
            int partCount = (int) (fileLength / partSize);
            if (fileLength % partSize != 0) {
                partCount++;
            }
            System.out.println("分片数为：" + partCount);
            // 遍历分片上传。
            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(objectName);
                uploadPartRequest.setUploadId(uploadId);
                // 设置上传的分片流。
                // 以本地文件为例说明如何创建FIleInputstream，并通过InputStream.skip()方法跳过指定数据。
                InputStream instream = new FileInputStream(sampleFile);
                instream.skip(startPos);
                uploadPartRequest.setInputStream(instream);
                // 设置分片大小。除了最后一个分片没有大小限制，其他的分片最小为100 KB。
                uploadPartRequest.setPartSize(curPartSize);
                // 设置分片号。每一个上传的分片都有一个分片号，取值范围是1~10000，如果超出此范围，OSS将返回InvalidArgument错误码。
                uploadPartRequest.setPartNumber( i + 1);
                // 每个分片不需要按顺序上传，甚至可以在不同客户端上传，OSS会按照分片号排序组成完整的文件。
                UploadPartResult uploadPartResult = ossClient.uploadPart(uploadPartRequest);
                // 每次上传分片之后，OSS的返回结果包含PartETag。PartETag将被保存在partETags中。
                partETags.add(uploadPartResult.getPartETag());
            }


            // 创建CompleteMultipartUploadRequest对象。
            // 在执行完成分片上传操作时，需要提供所有有效的partETags。OSS收到提交的partETags后，会逐一验证每个分片的有效性。当所有的数据分片验证通过后，OSS将把这些分片组合成一个完整的文件。
            CompleteMultipartUploadRequest completeMultipartUploadRequest =
                    new CompleteMultipartUploadRequest(bucketName, objectName, uploadId, partETags);

            // 如果需要在完成分片上传的同时设置文件访问权限，请参考以下示例代码。
            // completeMultipartUploadRequest.setObjectACL(CannedAccessControlList.Private);
            // 指定是否列举当前UploadId已上传的所有Part。仅在Java SDK为3.14.0及以上版本时，支持通过服务端List分片数据来合并完整文件时，将CompleteMultipartUploadRequest中的partETags设置为null。
            // Map<String, String> headers = new HashMap<String, String>();
            // 如果指定了x-oss-complete-all:yes，则OSS会列举当前UploadId已上传的所有Part，然后按照PartNumber的序号排序并执行CompleteMultipartUpload操作。
            // 如果指定了x-oss-complete-all:yes，则不允许继续指定body，否则报错。
            // headers.put("x-oss-complete-all","yes");
            // completeMultipartUploadRequest.setHeaders(headers);

            // 完成分片上传。
            CompleteMultipartUploadResult completeMultipartUploadResult = ossClient.completeMultipartUpload(completeMultipartUploadRequest);
            System.out.println(completeMultipartUploadResult.getETag());
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

2、并行分片上传

官网只有python版本代码

import os
from oss2 import determine_part_size, SizedFileAdapter
from oss2.models import PartInfo
import oss2
from concurrent.futures import ThreadPoolExecutor
from oss2.credentials import EnvironmentVariableCredentialsProvider


# 从环境变量中获取访问凭证。运行本代码示例之前，请确保已设置环境变量OSS_ACCESS_KEY_ID和OSS_ACCESS_KEY_SECRET。
auth = oss2.ProviderAuthV4(EnvironmentVariableCredentialsProvider())

# 填写Bucket所在地域对应的Endpoint。以华东1（杭州）为例，Endpoint填写为https://oss-cn-hangzhou.aliyuncs.com。
endpoint = "https://oss-cn-hangzhou.aliyuncs.com"

# 填写Endpoint对应的Region信息，例如cn-hangzhou。注意，v4签名下，必须填写该参数
region = "cn-hangzhou"

# yourBucketName填写存储空间名称。
bucket = oss2.Bucket(auth, endpoint, "yourbucketname", region=region)

# 填写不能包含Bucket名称在内的Object完整路径，例如exampledir/exampleobject.txt。
key = 'exampledir/exampleobject.txt'

# 填写本地文件的完整路径（待上传文件）
filename = 'D:\localpath\examplefile.txt'


def upload_part(filename, bucket, key, upload_id, part_number, offset, num_to_upload):
    """
    执行单个分片的上传操作
    :param filename: 本地文件路径
    :param bucket: oss2.Bucket 对象，表示OSS存储空间
    :param key: 上传文件的Object名称
    :param upload_id: 分片上传的唯一标识符
    :param part_number: 当前分片的编号
    :param offset: 当前分片的起始位置
    :param num_to_upload: 当前分片的大小
    :return: PartInfo 对象，包含分片的ETag和编号
    """
    with open(filename, 'rb') as fileobj:
        fileobj.seek(offset)
        result = bucket.upload_part(
            key,
            upload_id,
            part_number,
            SizedFileAdapter(fileobj, num_to_upload)
        )
    return PartInfo(part_number, result.etag)



def main():
    """
    主函数，执行文件上传流程
    """

    # 获取待上传文件的大小
    total_size = os.path.getsize(filename)
    # 设定分片大小为100KB，可根据需要调整
    part_size = determine_part_size(total_size, preferred_size=100 * 1024)  

    # 初始化分片上传，返回upload_id
    upload_id = bucket.init_multipart_upload(key).upload_id
    part_info_list = []

    # 创建线程池，设置最大并发数为8，可根据实际情况调整
    max_workers = 8  
    with ThreadPoolExecutor(max_workers=max_workers) as executor:
        futures = []
        part_number = 1
        offset = 0

        # 循环上传所有分片
        while offset < total_size:
            num_to_upload = min(part_size, total_size - offset)
            # 提交上传任务到线程池
            futures.append(
                executor.submit(upload_part, filename, bucket, key, upload_id, part_number, offset, num_to_upload)
            )
            offset += num_to_upload
            part_number += 1

        # 获取每个任务的返回结果（PartInfo对象），并将其添加到part_info_list中
        for future in futures:
            part_info_list.append(future.result())

    # 完成分片上传并返回结果
    bucket.complete_multipart_upload(key, upload_id, part_info_list)
    print(f'Upload completed for {key}')  # 输出上传完成的文件名


if __name__ == "__main__":
    main()  # 执行上传操作

断点续传上传

上手操作

package com.example.lzxoss;

import com.aliyun.oss.OSS;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import com.aliyun.oss.model.*;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

public class Demo3 {
    public static void main(String[] args) throws IOException {
        String endpoint;
        String bucketName;
        // 替换为您的 Bucket 区域
        String region = "cn-shenzhen";
        String AccessKey;
        String AccessKeySecret;
        String Folder;
        // 加载配置文件
        Properties prop = new Properties();
        try (InputStream input = OssJavaSdkQuickStart.class.getClassLoader().getResourceAsStream("aliyunoss.properties")) {
            if (input == null) {
                System.out.println("无法找到 aliyunoss.properties 文件");
                return;
            }
            prop.load(input);

            // 读取配置
            AccessKey = prop.getProperty("ACCESS_KEY_ID");
            AccessKeySecret = prop.getProperty("ACCESS_KEY_SECRET");
            endpoint = prop.getProperty("ENDPOINT");
            bucketName = prop.getProperty("BUCKET_NAME");
            Folder = prop.getProperty("FOLDER");

        }

        DefaultCredentialProvider defaultCredentialProvider = new DefaultCredentialProvider(AccessKey, AccessKeySecret);
        // 创建OSSClient实例。
        OSS ossClient = new OSSClientBuilder().build(endpoint, defaultCredentialProvider);
        try {

            ObjectMetadata meta = new ObjectMetadata();
            // 指定上传的内容类型。
            meta.setContentType("text/plain");

            // 文件上传时设置访问权限ACL。
            // meta.setObjectAcl(CannedAccessControlList.Private);

            // 通过UploadFileRequest设置多个参数。
            // 依次填写Bucket名称（例如examplebucket）以及Object完整路径（例如exampledir/exampleobject.txt），Object完整路径中不能包含Bucket名称。
            UploadFileRequest uploadFileRequest = new UploadFileRequest("lzxoss",Folder+"大文件.xmind");

            // 通过UploadFileRequest设置单个参数。
            // 填写本地文件的完整路径，例如D:\localpath\examplefile.txt。如果未指定本地路径，则默认从示例程序所属项目对应本地路径中上传文件。
//            uploadFileRequest.setUploadFile("C:////Users//罗泽轩//Desktop//实习记录//学习记录.docx");
            uploadFileRequest.setUploadFile("C:////Users//罗泽轩//Desktop//实习记录//ERP2.0学习记录.xmind");
            // 指定上传并发线程数，默认值为1。
            uploadFileRequest.setTaskNum(5);
            // 指定上传的分片大小，单位为字节，取值范围为100 KB~5 GB。默认值为100 KB。
            uploadFileRequest.setPartSize(1 * 1024 * 1024);
            // 开启断点续传，默认关闭。
            uploadFileRequest.setEnableCheckpoint(true);
            // 记录本地分片上传结果的文件。上传过程中的进度信息会保存在该文件中，如果某一分片上传失败，再次上传时会根据文件中记录的点继续上传。上传完成后，该文件会被删除。
            // 如果未设置该值，默认与待上传的本地文件同路径，名称为${uploadFile}.ucp。
            uploadFileRequest.setCheckpointFile("D:////断点续传记录文件.ucp");
            // 文件的元数据。
            uploadFileRequest.setObjectMetadata(meta);
            // 设置上传回调，参数为Callback类型。
            //uploadFileRequest.setCallback("yourCallbackEvent");

            // 断点续传上传。
            ossClient.uploadFile(uploadFileRequest);

        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (Throwable ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            // 关闭OSSClient。
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

模拟突发异常中断（上传过程中产生ucp文件，上传顺利完成后删除该文件，如果被中断了则会保留该文件）

文件下载

简单下载

权限设置方式同上

上手操作

package com.example.lzxoss;

import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import com.aliyun.oss.model.GetObjectRequest;
import java.io.File;
import java.io.InputStream;
import java.util.Properties;

public class Demo2 {

    public static void main(String[] args) throws Exception {
        String endpoint;
        String bucketName;
        // 替换为您的 Bucket 区域
        String region = "cn-shenzhen";
        String AccessKey;
        String AccessKeySecret;
        String Folder;
        // 加载配置文件
        Properties prop = new Properties();
        try (InputStream input = OssJavaSdkQuickStart.class.getClassLoader().getResourceAsStream("aliyunoss.properties")) {
            if (input == null) {
                System.out.println("无法找到 aliyunoss.properties 文件");
                return;
            }
            prop.load(input);

            // 读取配置
            AccessKey = prop.getProperty("ACCESS_KEY_ID");
            AccessKeySecret = prop.getProperty("ACCESS_KEY_SECRET");
            endpoint = prop.getProperty("ENDPOINT");
            bucketName = prop.getProperty("BUCKET_NAME");
            Folder = prop.getProperty("FOLDER");

        }

        DefaultCredentialProvider defaultCredentialProvider = new DefaultCredentialProvider(AccessKey, AccessKeySecret);

        // 创建OSSClient实例。
        OSS ossClient = new OSSClientBuilder().build(endpoint, defaultCredentialProvider);

        // 填写不包含Bucket名称在内的Object完整路径，例如testfolder/exampleobject.txt。
        String objectName = "images/大文件.xmind";
        // 填写Object下载到本地的完整路径。
        String pathName = "D:////下载大文件.xmind";

        try {
            // 下载Object到本地文件，并保存到指定的本地路径中。如果指定的本地文件存在会覆盖，不存在则新建。
            // 如果未指定本地路径，则下载后的文件默认保存到示例程序所属项目对应本地路径中。
            ossClient.getObject(new GetObjectRequest(bucketName, objectName), new File(pathName));
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (ClientException ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

断点续传下载

上手操作

package com.example.lzxoss;

import com.aliyun.oss.OSS;
import com.aliyun.oss.common.auth.*;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import com.aliyun.oss.model.*;

import java.io.InputStream;
import java.util.Properties;

public class Demo4 {
    public static void main(String[] args) throws Exception {
        String endpoint;
        String bucketName;
        // 替换为您的 Bucket 区域
        String region = "cn-shenzhen";
        String AccessKey;
        String AccessKeySecret;
        String Folder;
        // 加载配置文件
        Properties prop = new Properties();
        try (InputStream input = OssJavaSdkQuickStart.class.getClassLoader().getResourceAsStream("aliyunoss.properties")) {
            if (input == null) {
                System.out.println("无法找到 aliyunoss.properties 文件");
                return;
            }
            prop.load(input);

            // 读取配置
            AccessKey = prop.getProperty("ACCESS_KEY_ID");
            AccessKeySecret = prop.getProperty("ACCESS_KEY_SECRET");
            endpoint = prop.getProperty("ENDPOINT");
            bucketName = prop.getProperty("BUCKET_NAME");
            Folder = prop.getProperty("FOLDER");

        }

        DefaultCredentialProvider defaultCredentialProvider = new DefaultCredentialProvider(AccessKey, AccessKeySecret);

        // 创建OSSClient实例。
        OSS ossClient = new OSSClientBuilder().build(endpoint, defaultCredentialProvider);

        // 填写Object完整路径，例如exampledir/exampleobject.txt。Object完整路径中不能包含Bucket名称。
        String objectName = Folder + "大文件.xmind";

        try {
            // 请求10个任务并发下载。
            DownloadFileRequest downloadFileRequest = new DownloadFileRequest(bucketName, objectName);
            // 指定Object下载到本地文件的完整路径，例如D:\localpath\examplefile.txt。
            downloadFileRequest.setDownloadFile("D:////下载大文件.xmind");
            // 设置分片大小，单位为字节，取值范围为100 KB~5 GB。默认值为100 KB。
            downloadFileRequest.setPartSize(1 * 1024 * 1024);
            // 设置分片下载的并发数，默认值为1。
            downloadFileRequest.setTaskNum(10);
            // 开启断点续传下载，默认关闭。
            downloadFileRequest.setEnableCheckpoint(true);
            // 设置断点记录文件的完整路径，例如D:\localpath\examplefile.txt.dcp。
            // 只有当Object下载中断产生了断点记录文件后，如果需要继续下载该Object，才需要设置对应的断点记录文件。下载完成后，该文件会被删除。
            //downloadFileRequest.setCheckpointFile("D:\localpath\examplefile.txt.dcp");

            // 下载文件。
            DownloadFileResult downloadRes = ossClient.downloadFile(downloadFileRequest);
            // 下载成功时，会返回文件元数据。
            ObjectMetadata objectMetadata = downloadRes.getObjectMetadata();
            System.out.println(objectMetadata.getETag());
            System.out.println(objectMetadata.getLastModified());
            System.out.println(objectMetadata.getUserMetadata().get("meta"));
        } catch (OSSException oe) {
            System.out.println("Caught an OSSException, which means your request made it to OSS, "
                    + "but was rejected with an error response for some reason.");
            System.out.println("Error Message:" + oe.getErrorMessage());
            System.out.println("Error Code:" + oe.getErrorCode());
            System.out.println("Request ID:" + oe.getRequestId());
            System.out.println("Host ID:" + oe.getHostId());
        } catch (Throwable ce) {
            System.out.println("Caught an ClientException, which means the client encountered "
                    + "a serious internal problem while trying to communicate with OSS, "
                    + "such as not being able to access the network.");
            System.out.println("Error Message:" + ce.getMessage());
        } finally {
            if (ossClient != null) {
                ossClient.shutdown();
            }
        }
    }
}

下载过程中会产生dcp文件，下载顺利完成（无中断）后删除该文件