public R list(){
        Date date = new Date(System.currentTimeMillis()+1000*60*15*4*8);
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd‘T‘HH:mm:ss.SSS‘Z‘");
        Date oldDate = new Date(date.getTime()-1000*60*15);
        System.out.println(sdf.format(oldDate));
        System.out.println(sdf.format(new Date()));
        //Query query = new Query(Criteria.where("createTime").lte(oldDate));
        Query query = new Query(Criteria.where("createTime").gte(oldDate).lte(date)).with(Sort.by(Sort.Order.desc("createTime")));;
        List<AisShipRealtimeEntity> result = mongoTemplate.find(query,AisShipRealtimeEntity.class);
        List<AisShipRealtimeEntity> list= result.stream().collect(
                Collectors.collectingAndThen(
                         Collectors.toCollection(() -> new TreeSet<>(Comparator.comparing(AisShipRealtimeEntity::getShipMmsi))), ArrayList::new)
        );
        System.out.println(list.size());
        return R.ok(list);
    }