Auto set fields in spring data mongodb

I have a Base Entity class which all my Spring Data MongoDB classes extend, I want to have a few basic fields (check below) which need to be auto-set/auto-updated, what's the cleanest way to achieve this?

public class BaseEntity {
    @Id
    private ObjectId id;
    private Instant createdOn;
    private Instant updatedOn;
}

I'm using Spring Boot 3.x and Java 17.

Yes, you can achieve this using Spring Data MongoDB support. Here's how to set up:

1 - Define a base class with auditing annotations:

public class BaseEntity {

    @Id
    private ObjectId id;

    @CreatedDate
    private Instant createdOn;

    @LastModifiedDate
    private Instant updatedOn;
}

Your entities can simply extend this base class:

@Document(collection = "concrete")
public class ConcreteEntity extends BaseEntity {
    ...
}

2 - Enable auditing in your main application class:

@SpringBootApplication
@EnableMongoAuditing
public class ShowcaseApplication {
    public static void main(String[] args) {
       SpringApplication.run(ShowcaseApplication.class, args);
    }
}

That's it! Spring will automatically populate createdOn and updatedOn when the document is inserted.