如何将带有一长串通用列的表映射到JPA实体

Question

Consider this use case : a mysql table X and a java JPA entiy X.

create table X 
(id int(11),
 name varchar(200),
 value1 bigint(16),
 value2 bigint(16),
 value3 bigint(16),
 .
 .
 value100 bigint(16));

I would like to map to an entity like this :

@Entity("x")
@Table("x")
public class X {

@Id
@Column("id)
public int getId ...

@Column("name")
public String getName ..

@SomeMagicalExpression
public List<Long> getValues()..
}

I am well aware of the option to create a join table where each value is a row, I am trying to get away from performing joins. I would really hate to create a 100 getters and setters.

Answer 1

Bit of a shot in the dark, but maybe the OpenJPA @Columns annotation will suit your needs..

http://docs.oracle.com/html/E24396_01/ref_guide_mapping_custom.html#ref_guide_mapping_custom_field_conf_extex

Not sure if you could use it to map multiple columns to a collection though.. Maybe subclass ArrayList and override its constructor to take in a number of values to populate the list. (If my assumption that the values used in @Columns must correspond to a constructor is correct..)