云盒Bucket内的文件（Object）默认按照字母序排列。您可以结合实际场景列举当前云盒Bucket的所有Object、指定前缀的Object、指定个数的Object等。
使用阿里云SDK
仅支持通过Java SDK列举云盒Bucket内的所有Object，Java SDK要求3.15.0及以上版本。
import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import com.aliyun.oss.model.*;
import java.util.List;
import com.aliyun.oss.common.auth.DefaultCredentialProvider;
import com.aliyun.oss.common.comm.SignVersion;
import com.aliyun.oss.ClientBuilderConfiguration;
import com.aliyun.oss.common.auth.CredentialsProviderFactory;
import com.aliyun.oss.common.auth.EnvironmentVariableCredentialsProvider;
public class Demo {
public static void main(String[] args) throws Exception {
// 填写云盒Bucket的数据域名。
String endpoint = "https://cb-f8z7yvzgwfkl9q0h****.cn-heyuan.oss-cloudbox.aliyuncs.com";
// 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。
EnvironmentVariableCredentialsProvider credentialsProvider = CredentialsProviderFactory.newEnvironmentVariableCredentialsProvider();
// 填写云盒Bucket名称，例如examplebucket。
String bucketName = "examplebucket";
// 填写云盒Bucket所在地域。
String region = "cn-hangzhou";
// 填写云盒ID。
String cloudBoxId = "cb-f8z7yvzgwfkl9q0h****";
// 指定前缀，例如exampledir/object。
String keyPrefix = "exampledir/object";
// 创建OSSClient实例。
ClientBuilderConfiguration conf = new ClientBuilderConfiguration();
conf.setSignatureVersion(SignVersion.V4);
OSS ossClient = OSSClientBuilder.create()
.endpoint(endpoint)
.credentialsProvider(new DefaultCredentialProvider(credentialsProvider.getCredentials()))
.clientConfiguration(conf)
.region(region)
.cloudBoxId(cloudBoxId)
.build();
try {
// 列举Object。如果不设置keyPrefix，则列举云盒Bucket下的所有Object。如果设置keyPrefix，则列举包含指定前缀的Object。
ObjectListing objectListing = ossClient.listObjects(bucketName, keyPrefix);
List<OSSObjectSummary> sums = objectListing.getObjectSummaries();
for (OSSObjectSummary s : sums) {
System.out.println("\t" + s.getKey());
}
} 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();
}
}
}
} 使用命令行工具ossutil
关于使用ossutil列举Object的具体操作， 请参见列举Object。
使用REST API
如果您的程序自定义要求较高，您可以直接发起REST API请求。直接发起REST API请求需要手动编写代码计算签名。
您可以通过API中的GetBucket (ListObjects)或ListObjectsV2（GetBucketV2）接口列举Bucket中的Object。建议您在开发应用程序时使用较新的版本GetBucketV2 (ListObjectsV2)。为保证向后兼容性，OSS继续支持GetBucket (ListObjects)。