javax.persistence.CollectionTable - JPA annotation
javax.persistence
Annotation CollectionTable
- Target:
- Fields (including property get methods)
By default, the columns of the collection table that correspond to the embeddable class or basic type are derived from the attributes of the embeddable class or from the basic type according to the default values of the Column
annotation. In the case of a basic type, the column name is derived from the name of the collection-valued field or property. In the case of an embeddable class, the column names are derived from the field or property names of the embeddable class.
- To override the default properties of the column used for a basic type, the
Column
annotation is used on the collection-valued attribute in addition to theElementCollection
annotation. - To override these defaults for an embeddable class, the
AttributeOverride
and/orAttributeOverrides
annotations can be used in addition to theElementCollection
annotation. If the embeddable class contains references to other entities, the default values for the columns corresponding to those references may be overridden by means of theAssociationOverride
and/orAssociationOverrides
annotations.
If the CollectionTable
annotation is missing, the default values of the CollectionTable
annotation elements apply.
Example:
@Embeddable public class Address { protected String street; protected String city; protected String state; ... } @Entity public class Person { @Id protected String ssn; protected String name; protected Address home; ... @ElementCollection // use default table (PERSON_NICKNAMES) @Column(name="name", length=50) protected Set nickNames = new HashSet(); ... } @Entity public class WealthyPerson extends Person { @ElementCollection @CollectionTable(name="HOMES") // use default join column name @AttributeOverrides({ @AttributeOverride(name="street", column=@Column(name="HOME_STREET")), @AttributeOverride(name="city", column=@Column(name="HOME_CITY")), @AttributeOverride(name="state", column=@Column(name="HOME_STATE")) }) protected Set vacationHomes = new HashSet(); ... }
- Since:
- JPA 2.0
- Default value:
- ""
- Since:
- JPA 2.0
JoinColumn
(i.e., the concatenation of the following: the name of the entity; "_"; the name of the referenced primary key column.) However, if there is more than one join column, a JoinColumn
annotation must be specified for each join column using the JoinColumns
annotation. In this case, both the name
and the referencedColumnName
elements must be specified in each such JoinColumn
annotation. - Default value:
- {}
- Since:
- JPA 2.0
- Default value:
- ""
- Since:
- JPA 2.0
- Default value:
- ""
- Since:
- JPA 2.0
- Default value:
- {}
- Since:
- JPA 2.0