| /******************************************************************************* |
| * Copyright (c) 2008 - 2015 Oracle Corporation. All rights reserved. |
| * |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0 |
| * which accompanies this distribution. |
| * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html |
| * and the Eclipse Distribution License is available at |
| * http://www.eclipse.org/org/documents/edl-v10.php. |
| * |
| * Contributors: |
| * Petros Splinakis - Java Persistence 2.2 |
| * Linda DeMichiel - Java Persistence 2.1 |
| * Linda DeMichiel - Java Persistence 2.0 |
| * |
| ******************************************************************************/ |
| package javax.persistence; |
| |
| import java.lang.annotation.Repeatable; |
| 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.ElementType.TYPE; |
| import static java.lang.annotation.RetentionPolicy.RUNTIME; |
| import static javax.persistence.ConstraintMode.PROVIDER_DEFAULT; |
| |
| /** |
| * Specifies a primary key column that is used as a foreign key to |
| * join to another table. |
| * |
| * <p> It is used to join the primary table of an entity subclass |
| * in the {@link InheritanceType#JOINED JOINED} mapping strategy |
| * to the primary table of its superclass; it is used within a |
| * {@link SecondaryTable} annotation to join a secondary table |
| * to a primary table; and it may be used in a {@link OneToOne} |
| * mapping in which the primary key of the referencing entity |
| * is used as a foreign key to the referenced entity. |
| * |
| * <p> If no <code>PrimaryKeyJoinColumn</code> annotation is |
| * specified for a subclass in the <code>JOINED</code> |
| * mapping strategy, the foreign key columns are assumed |
| * to have the same names as the primary key columns of the |
| * primary table of the superclass. |
| * |
| * <pre> |
| * |
| * Example: Customer and ValuedCustomer subclass |
| * |
| * @Entity |
| * @Table(name="CUST") |
| * @Inheritance(strategy=JOINED) |
| * @DiscriminatorValue("CUST") |
| * public class Customer { ... } |
| * |
| * @Entity |
| * @Table(name="VCUST") |
| * @DiscriminatorValue("VCUST") |
| * @PrimaryKeyJoinColumn(name="CUST_ID") |
| * public class ValuedCustomer extends Customer { ... } |
| * </pre> |
| * |
| * @see SecondaryTable |
| * @see Inheritance |
| * @see OneToOne |
| * @see ForeignKey |
| * |
| * @since Java Persistence 1.0 |
| */ |
| @Repeatable(PrimaryKeyJoinColumns.class) |
| @Target({TYPE, METHOD, FIELD}) |
| @Retention(RUNTIME) |
| |
| public @interface PrimaryKeyJoinColumn { |
| |
| /** |
| * (Optional) The name of the primary key column of the current table. |
| * <p> Defaults to the same name as the primary key column |
| * of the primary table of the superclass (<code>JOINED</code> mapping strategy); the same |
| * name as the primary key column of the primary table |
| * (<code>SecondaryTable</code> mapping); or the same name as the |
| * primary key column for the table for the referencing entity |
| * (<code>OneToOne</code> mapping). |
| */ |
| String name() default ""; |
| |
| /** |
| * (Optional) The name of the primary key column of the table |
| * being joined to. <p> Defaults to the same name as the primary |
| * key column of the primary table of the superclass |
| * (<code>JOINED</code> mapping strategy); the same name as the |
| * primary key column of the primary table |
| * (<code>SecondaryTable</code> mapping); or the same name as the |
| * primary key column for the table for the referencing entity |
| * (<code>OneToOne</code> mapping). |
| */ |
| String referencedColumnName() default ""; |
| |
| /** |
| * (Optional) The SQL fragment that is used when generating the |
| * DDL for the column. This should not be specified for a |
| * <code>OneToOne</code> primary key association. |
| * <p> Defaults to the generated SQL to create a column of the |
| * inferred type. |
| */ |
| String columnDefinition() default ""; |
| |
| /** |
| * (Optional) Used to specify or control the generation of a |
| * foreign key constraint for the primary key join column |
| * when table generation is in effect. If |
| * this element is not specified, the persistence provider's |
| * default foreign key strategy will apply. |
| * |
| * @since Java Persistence 2.1 |
| */ |
| ForeignKey foreignKey() default @ForeignKey(PROVIDER_DEFAULT); |
| } |