private TimestampData convertToTimestamp(BsonValue docObj) {
        if (docObj.isDateTime()) {
            return TimestampData.fromLocalDateTime(
                    convertInstantToLocalDateTime(convertToInstant(docObj.asDateTime())));
        }
        if (docObj.isTimestamp()) {
            return TimestampData.fromLocalDateTime(
                    convertInstantToLocalDateTime(convertToInstant(docObj.asTimestamp())));
        }

        throw new IllegalArgumentException(
                "Unable to convert to timestamp from unexpected value '"
                        + docObj
                        + "' of type "
                        + docObj.getBsonType());
    }
A conversion from TimeType to int describes the number of milliseconds of the day.
inlong-sort/sort-flink/sort-flink-v1.15/sort-connectors/mongodb-cdc/src/main/java/org/apache/inlong/sort/mongodb/MongoDBConnectorDeserializationSchema.java