Usa ListObjectsV2 con un AWS SDK

Elenca gli oggetti in un bucket di directory.

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.model.ListObjectsV2Request;
import software.amazon.awssdk.services.s3.model.ListObjectsV2Response;
import software.amazon.awssdk.services.s3.model.S3Exception;
import software.amazon.awssdk.services.s3.model.S3Object;

import java.nio.file.Path;
import java.util.List;
import java.util.stream.Collectors;

import static com.example.s3.util.S3DirectoryBucketUtils.createDirectoryBucket;
import static com.example.s3.util.S3DirectoryBucketUtils.createS3Client;
import static com.example.s3.util.S3DirectoryBucketUtils.deleteAllObjectsInDirectoryBucket;
import static com.example.s3.util.S3DirectoryBucketUtils.deleteDirectoryBucket;
import static com.example.s3.util.S3DirectoryBucketUtils.getFilePath;
import static com.example.s3.util.S3DirectoryBucketUtils.putDirectoryBucketObject;

    /**
     * Lists objects in the specified S3 directory bucket.
     *
     * @param s3Client   The S3 client used to interact with S3
     * @param bucketName The name of the directory bucket
     * @return A list of object keys in the bucket
     */
    public static List<String> listDirectoryBucketObjectsV2(S3Client s3Client, String bucketName) {
        logger.info("Listing objects in bucket: {}", bucketName);

        try {
            // Create a ListObjectsV2Request
            ListObjectsV2Request listObjectsV2Request = ListObjectsV2Request.builder()
                    .bucket(bucketName)
                    .build();

            // Retrieve the list of objects
            ListObjectsV2Response response = s3Client.listObjectsV2(listObjectsV2Request);

            // Extract and return the object keys
            return response.contents().stream()
                    .map(S3Object::key)
                    .collect(Collectors.toList());

        } catch (S3Exception e) {
            logger.error("Failed to list objects: {} - Error code: {}", e.awsErrorDetails().errorMessage(),
                    e.awsErrorDetails().errorCode());
            throw e;
        }
    }