javax.persistence.OneToOne Maven / Gradle / Ivy
/*
* The contents of this file are subject to the terms
* of the Common Development and Distribution License
* (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/CDDLv1.0.html or
* glassfish/bootstrap/legal/CDDLv1.0.txt.
* See the License for the specific language governing
* permissions and limitations under the License.
*
* When distributing Covered Code, include this CDDL
* Header Notice in each file and include the License file
* at glassfish/bootstrap/legal/CDDLv1.0.txt.
* If applicable, add the following below the CDDL Header,
* with the fields enclosed by brackets [] replaced by
* you own identifying information:
* "Portions Copyrighted [year] [name of copyright owner]"
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
*/
package javax.persistence;
import java.lang.annotation.Target;
import java.lang.annotation.Retention;
import javax.persistence.CascadeType;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;
import static javax.persistence.FetchType.EAGER;
/**
* This annotation defines a single-valued association to
* another entity that has one-to-one multiplicity. It is not
* normally necessary to specify the associated target entity
* explicitly since it can usually be inferred from the type
* of the object being referenced.
*
*
* Example 1: One-to-one association that maps a foreign key column
*
* On Customer class:
*
* @OneToOne(optional=false)
* @JoinColumn(
* name="CUSTREC_ID", unique=true, nullable=false, updatable=false)
* public CustomerRecord getCustomerRecord() { return customerRecord; }
*
* On CustomerRecord class:
*
* @OneToOne(optional=false, mappedBy="customerRecord")
* public Customer getCustomer() { return customer; }
*
* Example 2: One-to-one association that assumes both the source and target share the same primary key values.
*
* On Employee class:
*
* @Entity
* public class Employee {
* @Id Integer id;
*
* @OneToOne @PrimaryKeyJoinColumn
* EmployeeInfo info;
* ...
* }
*
* On EmployeeInfo class:
*
* @Entity
* public class EmployeeInfo {
* @Id Integer id;
* ...
* }
*
*
* @since Java Persistence 1.0
*/
@Target({METHOD, FIELD})
@Retention(RUNTIME)
public @interface OneToOne {
/**
* (Optional) The entity class that is the target of
* the association.
*
* Defaults to the type of the field or property
* that stores the association.
*/
Class targetEntity() default void.class;
/**
* (Optional) The operations that must be cascaded to
* the target of the association.
*
*
By default no operations are cascaded.
*/
CascadeType[] cascade() default {};
/**
* (Optional) Whether the association should be lazily
* loaded or must be eagerly fetched. The {@link FetchType#EAGER EAGER}
* strategy is a requirement on the persistence provider runtime that
* the associated entity must be eagerly fetched. The {@link FetchType#LAZY
* LAZY} strategy is a hint to the persistence provider runtime.
*/
FetchType fetch() default EAGER;
/**
* (Optional) Whether the association is optional. If set
* to false then a non-null relationship must always exist.
*/
boolean optional() default true;
/** (Optional) The field that owns the relationship. This
* element is only specified on the inverse (non-owning)
* side of the association.
*/
String mappedBy() default "";
}