CassandraAttachmentOwnerDAO { public Flux<Username> retrieveOwners(AttachmentId attachmentId) { return executor.executeRows( selectStatement.bind() .setUUID(ID, attachmentId.asUUID())) .map(this::toOwner); } @Inject  CassandraAttachmentOwnerDAO(Session session); Mono<Void> addOwner(AttachmentId attachmentId, Username owner); Flux<Username> retrieveOwners(AttachmentId attachmentId);  }
@Test void retrieveOwnersShouldReturnEmptyByDefault() { assertThat(testee.retrieveOwners(ATTACHMENT_ID).toIterable()) .isEmpty(); }