Package io.github.joselion.springr2dbcrelationships.annotations

Annotation Interface OneToMany

@Documented
@Value("null")
@Retention(RUNTIME)
@Target({FIELD,PARAMETER,ANNOTATION_TYPE})
public @interface OneToMany

Marks a field to have a one-to-many relationship.

This annotation also adds the @Transient and @Value("null") annotations to the field.

Optional Element Summary

Optional Elements

Modifier and Type	Optional Element	Description
boolean	keepOrphans	Whether orphan entities are preserved or not.
boolean	linkOnly	Whether children entities are only linked to the parent or not.
String	mappedBy	Specifies the name of the "foreign key" column on the child table.
boolean	readonly	Whether the children entities are read-only or not, meaning they are never persisted or linked to the parent.
String	sortBy	Specifies the column used to sort the populated children entities.
org.springframework.data.domain.Sort.Direction	sortIn	Specifies in which direction the populated children entities are sorted.

Element Details

keepOrphans

boolean keepOrphans

Whether orphan entities are preserved or not. Defaults to false.

Usually, one-to-many relationships have a parent-children configuration, meaning every child needs a parent assigned to it. By default, the annotation will delete orphan entites, or children which are no longer assigned to their parent. You can prevent this behavior by setting this option to true, in which case the annotation will only remove the link of the orphan entities with the parent.

Returns:

true if orphan entities should be presereved, false otherwise

Default:

false

linkOnly

boolean linkOnly

Whether children entities are only linked to the parent or not. Defaults to false.

Link-only means the children entities should already exist. The annotation will only update the "foreign key" link on each entity when required. Other values in the children entities are never updated.

Returns:

true if children entities are only linked, false otherwise

Default:

false

mappedBy

String mappedBy

Specifies the name of the "foreign key" column on the child table. This is optional if the column's name matches the parent's table name followed by an _id suffix.

For example, given a parent table country and a child table city, the "foreign key" column of the city table will be inferred as country_id.

Returns:

the "foreign key" column name in the child table

Default:

""

readonly

boolean readonly

Whether the children entities are read-only or not, meaning they are never persisted or linked to the parent. Defaults to false.

Returns:

true if the children entities are read-only, false otherwise

Default:

false

sortBy

String sortBy

Specifies the column used to sort the populated children entities.

By default, the annotation tries to find the field associated with Auditable.getCreatedDate() or annotated with @CreatedDate. If none can be found, it'll try to find a "created_at" column as a last resort. If all of that fails, the children will be unsorted.

Returns:

the sorting column name

Default:

""

sortIn

org.springframework.data.domain.Sort.Direction sortIn

Specifies in which direction the populated children entities are sorted. Defaults to Sort.Direction.DESC.

Returns:

the sort direction

Default:

DESC