Java Architecture for XML Binding (JAXB) is a Java API that allows Java developers to map Java classes to XML representations.

jaxb-api-2.3.1.jar is the JAR file for the JAXB API 2.3 specification. You can download and use it directly without any building process as shown in the last tutorial.

If you want to rebuild the JAR file, you can download the source code at JAXB API Maven Website.

You can also browse the source code below:

⏎ javax/xml/bind/annotation/XmlIDREF.java

/*
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 *
 * Copyright (c) 2004-2017 Oracle and/or its affiliates. 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://oss.oracle.com/licenses/CDDL+GPL-1.1
 * or 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 LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
 * If applicable, add the following below the License Header, with the fields
 * enclosed by brackets [] replaced by your own identifying information:
 * "Portions Copyright [year] [name of copyright owner]"
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 * 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
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 * and therefore, elected the GPL Version 2 license, then the option applies
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 */

package javax.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.*;

/**
 * <p>
 * Maps a JavaBean property to XML IDREF.
 * 
 * <p>
 * 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. 
 *
 * <p><b>Usage</b> </p>
 * The {@code @XmlIDREF} annotation can be used with the following
 * program elements: 
 * <ul> 
 *   <li> a JavaBean property </li>
 *   <li> non static, non transient field </li>
 * </ul>
 * 
 * <p>See "Package Specification" in javax.xml.bind.package javadoc for
 * additional common information.</p>
 *
 * <p> The usage is subject to the following constraints:
 * <ul>
 *
 *   <li> 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}.  </li>
 *   <li> 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}.
 *        <p>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.
 *        </li>
 *   <li> This annotation can be used with the following annotations:
 *        {@link XmlElement}, {@link XmlAttribute}, {@link XmlList}, 
 *        and {@link XmlElements}.</li>  
 *
 * </ul>
 * <p><b>Example:</b> Map a JavaBean property to {@code xs:IDREF}
 *   (i.e. by reference rather than by containment)</p>
 * <pre>
 *
 *   //EXAMPLE: Code fragment
 *   public class Shipping {
 *       &#64;XmlIDREF public Customer getCustomer();
 *       public void setCustomer(Customer customer);
 *       ....
 *    }
 * {@code
 * 
 *   <!-- Example: XML Schema fragment -->
 *   <xs:complexType name="Shipping">
 *     <xs:complexContent>
 *       <xs:sequence>
 *         <xs:element name="customer" type="xs:IDREF"/>
 *         ....
 *       </xs:sequence>
 *     </xs:complexContent>
 *   </xs:complexType>
 *
 * }</pre>
 *
 *
 * <p><b>Example 2: </b> The following is a complete example of
 * containment versus reference.
 * 
 * <pre>
 *    // By default, Customer maps to complex type {@code xs:Customer}
 *    public class Customer {
 *        
 *        // map JavaBean property type to {@code xs:ID}
 *        &#64;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
 *       &#64;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
 *       &#64;XmlIDREF public Customer getCustomer();       
 *       public void setCustomer(Customer customer);
 *   }
 *
 *   // at least one class must reference Customer by containment;
 *   // Customer instances won't be marshalled.
 *   &#64;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
 * 
 *   <!-- XML Schema mapping for above code frament -->
 *
 *   <xs:complexType name="Invoice">
 *     <xs:complexContent>
 *       <xs:sequence>
 *         <xs:element name="customer" type="xs:IDREF"/>
 *         ....
 *       </xs:sequence>
 *     </xs:complexContent>
 *   </xs:complexType>
 *
 *   <xs:complexType name="Shipping">
 *     <xs:complexContent>
 *       <xs:sequence>
 *         <xs:element name="customer" type="xs:IDREF"/>
 *         ....
 *       </xs:sequence>
 *     </xs:complexContent>
 *   </xs:complexType>
 *
 *   <xs:complexType name="Customer">
 *     <xs:complexContent>
 *       <xs:sequence>
 *         ....
 *       </xs:sequence>
 *       <xs:attribute name="CustomerID" type="xs:ID"/>
 *     </xs:complexContent>
 *   </xs:complexType>
 *
 *   <xs:complexType name="CustomerData">
 *     <xs:complexContent>
 *       <xs:sequence>
 *         <xs:element name="customer" type="xs:Customer"/>
 *         <xs:element name="shipping" type="xs:Shipping"/>
 *         <xs:element name="invoice"  type="xs:Invoice"/>
 *       </xs:sequence>
 *     </xs:complexContent>
 *   </xs:complexType>
 *
 *   <xs:element name"customerData" type="xs:CustomerData"/>
 *
 *   <!-- Instance document conforming to the above XML Schema -->
 *    <customerData>
 *       <customer customerID="Alice">
 *           ....
 *       </customer>
 *
 *       <shipping customer="Alice">
 *           ....
 *       </shipping>
 *         
 *       <invoice customer="Alice">
 *           ....
 *       </invoice>
 *   </customerData>
 *
 * }</pre>
 *
 * <p><b>Example 3: </b> Mapping List to repeating element of type IDREF
 * <pre>
 *     // Code fragment
 *     public class Shipping {
 *         &#64;XmlIDREF
 *         &#64;XmlElement(name="Alice")
 *             public List customers;
 *     }
 * {@code
 * 
 *     <!-- XML schema fragment -->
 *     <xs:complexType name="Shipping">
 *       <xs:sequence>
 *         <xs:choice minOccurs="0" maxOccurs="unbounded">
 *           <xs:element name="Alice" type="xs:IDREF"/>
 *         </xs:choice>
 *       </xs:sequence>
 *     </xs:complexType>
 * }</pre>
 *
 * <p><b>Example 4: </b> Mapping a List to a list of elements of type IDREF.
 * <pre>
 *     //Code fragment
 *     public class Shipping {
 *         &#64;XmlIDREF
 *         &#64;XmlElements(
 *             &#64;XmlElement(name="Alice", type="Customer.class")
 *              &#64;XmlElement(name="John", type="InternationalCustomer.class")
 *         public List customers;
 *     }
 * {@code
 * 
 *     <!-- XML Schema fragment -->
 *     <xs:complexType name="Shipping">
 *       <xs:sequence>
 *         <xs:choice minOccurs="0" maxOccurs="unbounded">
 *           <xs:element name="Alice" type="xs:IDREF"/>
 *           <xs:element name="John" type="xs:IDREF"/>
 *         </xs:choice>
 *       </xs:sequence>
 *     </xs:complexType>
 * }</pre>
 * @author Sekhar Vajjhala, Sun Microsystems, Inc. 
 * @see XmlID
 * @since 1.6, JAXB 2.0
 */

@Retention(RUNTIME) @Target({FIELD, METHOD})
public @interface XmlIDREF {}

⏎ javax/xml/bind/annotation/XmlIDREF.java

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File name: jaxb-api-2.3.1-sources.jar
File size: 271123 bytes
Release date: 2018-10-10
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