@Override public int create(SensorTypeInfo sensor) { MongoCollection<Document> collection = CloudMongoDB.getInstance().getCollection("Drivers"); List<Document> values = new LinkedList<>(); for (MeasureValue sen : sensor.getValues()) { Map<String, Object> map = new HashMap<>(); map.put("name", sen.getName()); map.put("unit", sen.getUnit()); Document document = new Document(map); values.add(document); } Map<String, Object> map = new HashMap<>(); map.put("type", sensor.getType()); map.put("type_name", sensor.getTypeName()); map.put("driver_name", sensor.getDriverName()); map.put("values", values); Document doc = new Document(map); collection.insertOne(doc); return 0; }