jakarta.persistence.CollectionTable Maven / Gradle / Ivy
/*
* Copyright (c) 2008, 2020 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0,
* or the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
*/
// Contributors:
// Linda DeMichiel - 2.1
// Linda DeMichiel - 2.0
package jakarta.persistence;
import java.lang.annotation.Target;
import java.lang.annotation.Retention;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
/**
* Specifies the table that is used for the mapping of
* collections of basic or embeddable types. Applied
* to the collection-valued field or property.
*
* 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 the
* ElementCollection annotation.
*
* - To override these defaults for an embeddable class, the
*
AttributeOverride and/or
* AttributeOverrides annotations can be used in
* addition to the ElementCollection 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 the AssociationOverride and/or
* AssociationOverrides 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<String> 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<Address> vacationHomes = new HashSet();
* ...
* }
*
*
* @see ElementCollection
* @see AttributeOverride
* @see AssociationOverride
* @see Column
*
* @since 2.0
*/
@Target( { METHOD, FIELD })
@Retention(RUNTIME)
public @interface CollectionTable {
/**
* (Optional) The name of the collection table. If not specified,
* it defaults to the concatenation of the name of the containing
* entity and the name of the collection attribute, separated by
* an underscore.
*/
String name() default "";
/**
* (Optional) The catalog of the table. If not specified, the
* default catalog is used.
*/
String catalog() default "";
/**
* (Optional) The schema of the table. If not specified, the
* default schema for the user is used.
*/
String schema() default "";
/**
* (Optional) The foreign key columns of the collection table
* which reference the primary table of the entity. The default
* only applies if a single join column is used. The default is
* the same as for 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.
*/
JoinColumn[] joinColumns() default {};
/**
* (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. If both this element and the foreignKey
* element of any of the joinColumns elements are
* specified, the behavior is undefined. If no foreign key
* annotation element is specified in either location, the
* persistence provider's default foreign key strategy will
* apply.
*
* @since 2.1
*/
ForeignKey foreignKey() default @ForeignKey(ConstraintMode.PROVIDER_DEFAULT);
/**
* (Optional) Unique constraints that are to be placed on the
* table. These are only used if table generation is in effect.
*/
UniqueConstraint[] uniqueConstraints() default {};
/**
* (Optional) Indexes for the table. These are only used if
* table generation is in effect.
*
* @since 2.1
*/
Index[] indexes() default {};
}