jakarta.persistence.PrimaryKeyJoinColumns Maven / Gradle / Ivy
/*
* Copyright (c) 2008, 2023 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.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
/**
* Groups {@link PrimaryKeyJoinColumn} annotations.
* It is used to map composite foreign keys.
*
* Example: {@code ValuedCustomer} subclass
* {@snippet :
* @Entity
* @Table(name = "VCUST")
* @DiscriminatorValue("VCUST")
* @PrimaryKeyJoinColumns({
* @PrimaryKeyJoinColumn(name = "CUST_ID",
* referencedColumnName = "ID"),
* @PrimaryKeyJoinColumn(name = "CUST_TYPE",
* referencedColumnName = "TYPE")})
* public class ValuedCustomer extends Customer { ... }
* }
*
* @see ForeignKey
*
* @since 1.0
*/
@Target({TYPE, METHOD, FIELD})
@Retention(RUNTIME)
public @interface PrimaryKeyJoinColumns {
/**
* One or more {@link PrimaryKeyJoinColumn} annotations.
*/
PrimaryKeyJoinColumn[] value();
/**
* (Optional) Used to specify or control the generation of a
* foreign key constraint when table generation is in effect.
* If both this element and the {@code foreignKey} element of
* any of the {@link PrimaryKeyJoinColumn} elements are specified,
* the behavior is undefined. If no foreign key annotation element
* is specified in either location, a default foreign key strategy
* is selected by the persistence provider.
*
* @since 2.1
*/
ForeignKey foreignKey() default @ForeignKey(ConstraintMode.PROVIDER_DEFAULT);
}