public void deleteAll(User user, Conversation conversation) {
//		TODO: optimize
		messageRepository.getAllBySenderAndConversation(user, conversation)
				.stream()
				.parallel()
				.forEach(this::delete);
	}
public void deleteAll(User user, Conversation conversation) {
		messageRepository.getAllBySenderAndConversation(user, conversation)
				.stream()
				.parallel()
				.forEach(this::delete);
	}
public void deleteall(user user, conversation conversation) { messagerepository.getallbysenderandconversation(user, conversation) .stream() .parallel() .foreach(this::delete); }