jakarta.xml.bind.annotation.XmlIDREF Maven / Gradle / Ivy
/*
* Copyright (c) 2004, 2021 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0, which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package jakarta.xml.bind.annotation;
import java.lang.annotation.Target;
import java.lang.annotation.Retention;
import static java.lang.annotation.ElementType.*;
import static java.lang.annotation.RetentionPolicy.*;
/**
*
* Maps a JavaBean property to XML IDREF.
*
*
* To preserve referential integrity of an object graph across XML
* serialization followed by a XML deserialization, requires an object
* reference to be marshaled by reference or containment
* appropriately. Annotations {@code @XmlID} and {@code @XmlIDREF}
* together allow a customized mapping of a JavaBean property's
* type by containment or reference.
*
*
Usage
* The {@code @XmlIDREF} annotation can be used with the following
* program elements:
*
* - a JavaBean property
* - non static, non transient field
*
*
* See "Package Specification" in jakarta.xml.bind.package javadoc for
* additional common information.
*
* The usage is subject to the following constraints:
*
*
* - If the type of the field or property is a collection type,
* then the collection item type must contain a property or
* field annotated with {@code @XmlID}.
* - If the field or property is single valued, then the type of
* the property or field must contain a property or field
* annotated with {@code @XmlID}.
*
Note: If the collection item type or the type of the
* property (for non collection type) is java.lang.Object, then
* the instance must contain a property/field annotated with
* {@code @XmlID} attribute.
*
* - This annotation can be used with the following annotations:
* {@link XmlElement}, {@link XmlAttribute}, {@link XmlList},
* and {@link XmlElements}.
*
*
* Example: Map a JavaBean property to {@code xs:IDREF}
* (i.e. by reference rather than by containment)
*
*
* //EXAMPLE: Code fragment
* public class Shipping {
* @XmlIDREF public Customer getCustomer();
* public void setCustomer(Customer customer);
* ....
* }
* {@code
*
*
*
*
*
*
*
*
*
* }
*
*
* Example 2: The following is a complete example of
* containment versus reference.
*
*
* // By default, Customer maps to complex type {@code xs:Customer}
* public class Customer {
*
* // map JavaBean property type to {@code xs:ID}
* @XmlID public String getCustomerID();
* public void setCustomerID(String id);
*
* // .... other properties not shown
* }
*
*
* // By default, Invoice maps to a complex type {@code xs:Invoice}
* public class Invoice {
*
* // map by reference
* @XmlIDREF public Customer getCustomer();
* public void setCustomer(Customer customer);
*
* // .... other properties not shown here
* }
*
* // By default, Shipping maps to complex type {@code xs:Shipping}
* public class Shipping {
*
* // map by reference
* @XmlIDREF public Customer getCustomer();
* public void setCustomer(Customer customer);
* }
*
* // at least one class must reference Customer by containment;
* // Customer instances won't be marshalled.
* @XmlElement(name="CustomerData")
* public class CustomerData {
* // map reference to Customer by containment by default.
* public Customer getCustomer();
*
* // maps reference to Shipping by containment by default.
* public Shipping getShipping();
*
* // maps reference to Invoice by containment by default.
* public Invoice getInvoice();
* }
* {@code
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
* ....
*
*
*
*
*
*
*
*
*
*
*
*
*
* ....
*
*
*
* ....
*
*
*
* ....
*
*
*
* }
*
* Example 3: Mapping List to repeating element of type IDREF
*
* // Code fragment
* public class Shipping {
* @XmlIDREF
* @XmlElement(name="Alice")
* public List customers;
* }
* {@code
*
*
*
*
*
*
*
*
* }
*
* Example 4: Mapping a List to a list of elements of type IDREF.
*
* //Code fragment
* public class Shipping {
* @XmlIDREF
* @XmlElements(
* @XmlElement(name="Alice", type="Customer.class")
* @XmlElement(name="John", type="InternationalCustomer.class")
* public List customers;
* }
* {@code
*
*
*
*
*
*
*
*
* }
* @author Sekhar Vajjhala, Sun Microsystems, Inc.
* @see XmlID
* @since 1.6, JAXB 2.0
*/
@Retention(RUNTIME) @Target({FIELD, METHOD})
public @interface XmlIDREF {}