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 | Method and Description |
|---|---|
| public ForeignKey | foreignKey()
(Optional) Used to specify or control the generation of a
foreign key constraint for the columns corresponding to the
|
| public JoinColumn[] | |
| public JoinTable | |
| public 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. |
| foreignKey | back to summary |
|---|---|
| public ForeignKey foreignKey() (Optional) Used to specify or control the generation of a
foreign key constraint for the columns corresponding to the
| |
| joinColumns | back to summary |
|---|---|
| public JoinColumn[] joinColumns() The join column(s) being mapped to the persistent attribute(s).
The | |
| joinTable | back to summary |
|---|---|
| public JoinTable joinTable() The join table that maps the relationship.
The
| |
| name | back to summary |
|---|---|
| public 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. | |