javax.persistence.PrimaryKeyJoinColumn Maven / Gradle / Ivy
/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
*
* Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
*
* The contents of this file are subject to the terms of either the GNU
* General Public License Version 2 only ("GPL") or the Common Development
* and Distribution License("CDDL") (collectively, the "License"). You
* may not use this file except in compliance with the License. You can obtain
* a copy of the License at https://glassfish.dev.java.net/public/CDDL+GPL.html
* or glassfish/bootstrap/legal/LICENSE.txt. See the License for the specific
* language governing permissions and limitations under the License.
*
* When distributing the software, include this License Header Notice in each
* file and include the License file at glassfish/bootstrap/legal/LICENSE.txt.
* Sun designates this particular file as subject to the "Classpath" exception
* as provided by Sun in the GPL Version 2 section of the License file that
* accompanied this code. If applicable, add the following below the License
* Header, with the fields enclosed by brackets [] replaced by your own
* identifying information: "Portions Copyrighted [year]
* [name of copyright owner]"
*
* Contributor(s):
*
* If you wish your version of this file to be governed by only the CDDL or
* only the GPL Version 2, indicate your decision by adding "[Contributor]
* elects to include this software in this distribution under the [CDDL or GPL
* Version 2] license." If you don't indicate a single choice of license, a
* recipient has the option to distribute your version of this file under
* either the CDDL, the GPL Version 2 or to extend the choice of license to
* its licensees as provided above. However, if you add GPL Version 2 code
* and therefore, elected the GPL Version 2 license, then the option applies
* only if the new code is made subject to such option by the copyright
* holder.
*/
package javax.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.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
/**
* This annotation specifies a primary key column that is used
* as a foreign key to join to another table.
*
* 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.
*
*
If no PrimaryKeyJoinColumn annotation is
* specified for a subclass in the {@link InheritanceType#JOINED
* JOINED} 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
*
*
*
* 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 { ... }
*
*
* @since Java Persistence 1.0
*/
@Target({TYPE, METHOD, FIELD})
@Retention(RUNTIME)
public @interface PrimaryKeyJoinColumn {
/**
* The name of the primary key column of the current table.
* Defaults to the same name as the primary key column
* of the primary table of the superclass ({@link
* InheritanceType#JOINED JOINED} mapping strategy); the same
* name as the primary key column of the primary table
* ({@link SecondaryTable} mapping); or the same name as the
* primary key column for the table for the referencing entity
* ({@link OneToOne} mapping)
*/
String name() default "";
/**
* (Optional) The name of the primary key column of the table
* being joined to.
*
Defaults to the same name as the primary key column
* of the primary table of the superclass ({@link
* InheritanceType#JOINED JOINED} mapping strategy); the same
* name as the primary key column of the primary table
* ({@link SecondaryTable} mapping); or the same name as the
* primary key column for the table for the referencing entity
* ({@link OneToOne} 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
* {@link OneToOne} primary key association.
*
Defaults to the generated SQL to create a column of the
* inferred type.
*/
String columnDefinition() default "";
}