Упрощенная и обновленная версия ответа Scala от Паоло:
import scala.collection.JavaConversions.{collectionAsScalaIterable => asScala}
import com.amazonaws.services.s3.AmazonS3
import com.amazonaws.services.s3.model.{ListObjectsRequest, ObjectListing, S3ObjectSummary}
def buildListing(s3: AmazonS3, request: ListObjectsRequest): List[S3ObjectSummary] = {
def buildList(listIn: List[S3ObjectSummary], bucketList:ObjectListing): List[S3ObjectSummary] = {
val latestList: List[S3ObjectSummary] = bucketList.getObjectSummaries.toList
if (!bucketList.isTruncated) listIn ::: latestList
else buildList(listIn ::: latestList, s3.listNextBatchOfObjects(bucketList))
}
buildList(List(), s3.listObjects(request))
}
Удаление обобщенных элементов и использование ListObjectRequest, созданного сборщиками SDK.