Spring MongoRepository is updating or upserting instead of inserting

Question

I\'m using a :

org.springframework.data.mongodb.repository.MongoRepository

I start with an empty DB and create an object with _id = 1234<

Answer 1

the application shall update only when you have @Id annotation for one of the field, after long difficulty had found this

@Document(collection="bus")
public class Bus {

//  @Indexed(unique=true, direction=IndexDirection.DESCENDING, dropDups=true)
    @Id
    private String busTitle; 
    private int totalNoOfSeats;
    private int noOfSeatsAvailable; 
    private String busType; 
}

but somehow I could not use @Indexed(unique=true, direction=IndexDirection.DESCENDING, dropDups=true)