Support for datastax driver mapper

[Sammers21]

There is support for mappers in the latest major version of Datastax driver[1]. It works in the following way: you define :

1. an Entity:

@Entity
public class Product {

    @PartitionKey private UUID id;
    String description;
}

2. a DAO:

@Dao
public interface ProductDao {

    @Select
    Product findById(UUID productId);
}

3. a Mapper:

@Mapper
public interface InventoryMapper {
  @DaoFactory
  ProductDao productDao(@DaoKeyspace CqlIdentifier keyspace);
}

Then you extend the compiling process with annotation processing[2], and the processor autogenerates implementation for the interfaces, so you can use them.

The question is: how can we extend this annotation processor so we can declare the interfaces with Vert.x Futures.

[1] - https://docs.datastax.com/en/developer/java-driver/4.4/manual/mapper/
[2] - https://docs.datastax.com/en/developer/java-driver/4.4/manual/mapper/config/#configuring-the-annotation-processor