@Target(value={TYPE,METHOD,FIELD}) @Retention(value=RUNTIME) public @interface AssociationOverride
May be applied to an entity that extends a mapped superclass to override a relationship mapping defined by
the mapped superclass. If not specified, the association is mapped the same as in the original mapping.
When used to override a mapping defined by a mapped superclass, AssociationOverride
is applied
to the entity class.
May be used to override a relationship mapping from an embeddable within an entity to another entity when
the embeddable is on the owning side of the relationship. When used to override a relationship mapping
defined by an embeddable class (including an embeddable class embedded within another embeddable class),
AssociationOverride
is applied to the field or property containing the embeddable.
When AssociationOverride
is used to override a relationship mapping from an embeddable class,
the name
element specifies the referencing relationship field or property within the
embeddable class. To override mappings at multiple levels of embedding, a dot (".") notation syntax must be
used in the name
element to indicate an attribute within an embedded attribute. The value of
each identifier used with the dot notation is the name of the respective embedded field or property.
When AssociationOverride
is applied to override the mappings of an embeddable class used as a
map value, "value.
" must be used to prefix the name of the attribute within the embeddable
class that is being overridden in order to specify it as part of the map value.
If the relationship mapping is a foreign key mapping, the joinColumns
element is used. If the
relationship mapping uses a join table, the joinTable
element must be specified to override
the mapping of the join table and/or its join columns.
Example 1: Overriding the mapping of a relationship defined by a mapped superclass @MappedSuperclass public class Employee { ... @ManyToOne protected Address address; ... } @Entity @AssociationOverride(name="address", joinColumns=@JoinColumn(name="ADDR_ID")) // address field mapping overridden to ADDR_ID foreign key public class PartTimeEmployee extends Employee { ... }
Example 2: Overriding the mapping for phoneNumbers defined in the ContactInfo class @Entity public class Employee { @Id int id; @AssociationOverride( name="phoneNumbers", joinTable=@JoinTable( name="EMPPHONES", joinColumns=@JoinColumn(name="EMP"), inverseJoinColumns=@JoinColumn(name="PHONE") ) ) @Embedded ContactInfo contactInfo; ... } @Embeddable public class ContactInfo { @ManyToOne Address address; // Unidirectional @ManyToMany(targetEntity=PhoneNumber.class) List phoneNumbers; } @Entity public class PhoneNumber { @Id int number; @ManyToMany(mappedBy="contactInfo.phoneNumbers") Collection<Employee> employees; }
Embedded
,
Embeddable
,
MappedSuperclass
,
AttributeOverride
Modifier and Type | Required Element and Description |
---|---|
String |
name
(Required) The name of the relationship property whose mapping is being overridden if property-based
access is being used, or the name of the relationship field if field-based access is used.
|
Modifier and Type | Optional Element and Description |
---|---|
ForeignKey |
foreignKey
(Optional) Used to specify or control the generation of a foreign key constraint for the columns
corresponding to the joinColumns element when table generation is in effect.
|
JoinColumn[] |
joinColumns
The join column(s) being mapped to the persistent attribute(s).
|
JoinTable |
joinTable
The join table that maps the relationship.
|
public abstract String name
public abstract JoinColumn[] joinColumns
joinColumns
elements
must be specified if a foreign key mapping is used in the overriding of the mapping of the
relationship. The joinColumns
element must not be specified if a join table is used in the
overriding of the mapping of the relationship.public abstract JoinTable joinTable
joinTable
element must be specified if a
join table is used in the overriding of the mapping of the relationship. The joinTable
element must not be specified if a foreign key mapping is used in the overriding of the relationship.public abstract ForeignKey foreignKey
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