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/adapters/XmlJavaTypeAdapter.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:
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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
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 * 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
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 * holder.
 */

package javax.xml.bind.annotation.adapters;

import javax.xml.bind.annotation.XmlAnyElement;
import javax.xml.bind.annotation.XmlElementRefs;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlSchemaType;
import javax.xml.bind.annotation.XmlElementRef;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlSchema;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlSchemaTypes;
import java.lang.annotation.Target;
import java.lang.annotation.Retention;

import static java.lang.annotation.RetentionPolicy.RUNTIME;
import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.ElementType.PARAMETER;
import static java.lang.annotation.ElementType.PACKAGE;


/**
 * Use an adapter that implements {@link XmlAdapter} for custom marshaling.
 *
 * <p> <b> Usage: </b> </p>
 *
 * <p> The {@code @XmlJavaTypeAdapter} annotation can be used with the
 * following program elements:  
 * <ul> 
 *   <li> a JavaBean property </li>
 *   <li> field </li>
 *   <li> parameter </li>
 *   <li> package </li>
 *   <li> from within {@link XmlJavaTypeAdapters} </li>
 * </ul>
 *
 * <p> When {@code @XmlJavaTypeAdapter} annotation is defined on a
 * class, it applies to all references to the class.
 * <p> When {@code @XmlJavaTypeAdapter} annotation is defined at the
 * package level it applies to all references from within the package
 * to {@code @XmlJavaTypeAdapter.type()}.
 * <p> When {@code @XmlJavaTypeAdapter} annotation is defined on the
 * field, property or parameter, then the annotation applies to the
 * field, property or the parameter only.
 * <p> A {@code @XmlJavaTypeAdapter} annotation on a field, property
 * or parameter overrides the {@code @XmlJavaTypeAdapter} annotation
 * associated with the class being referenced by the field, property
 * or parameter.  
 * <p> A {@code @XmlJavaTypeAdapter} annotation on a class overrides
 * the {@code @XmlJavaTypeAdapter} annotation specified at the
 * package level for that class.
 *
 * <p>This annotation can be used with the following other annotations:
 * {@link XmlElement}, {@link XmlAttribute}, {@link XmlElementRef},
 * {@link XmlElementRefs}, {@link XmlAnyElement}. This can also be
 * used at the package level with the following annotations:
 * {@link XmlAccessorType}, {@link XmlSchema}, {@link XmlSchemaType},
 * {@link XmlSchemaTypes}. 
 * 
 * <p><b> Example: </b> See example in {@link XmlAdapter}
 *
 * @author <ul><li>Sekhar Vajjhala, Sun Microsystems Inc.</li> <li> Kohsuke Kawaguchi, Sun Microsystems Inc.</li></ul>
 * @since 1.6, JAXB 2.0
 * @see XmlAdapter
 */

@Retention(RUNTIME) @Target({PACKAGE,FIELD,METHOD,TYPE,PARAMETER})        
public @interface XmlJavaTypeAdapter {
    /**
     * Points to the class that converts a value type to a bound type or vice versa.
     * See {@link XmlAdapter} for more details.
     */
    Class<? extends XmlAdapter> value();

    /**
     * If this annotation is used at the package level, then value of
     * the type() must be specified.
     */

    Class type() default DEFAULT.class;

    /**
     * Used in {@link XmlJavaTypeAdapter#type()} to
     * signal that the type be inferred from the signature
     * of the field, property, parameter or the class.
     */

    static final class DEFAULT {}
    
}

⏎ javax/xml/bind/annotation/adapters/XmlJavaTypeAdapter.java

Or download all of them as a single archive file:

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

⇒ Download JAXB 2.2 Specification and API JAR

⇐ Download JAXB 2.3 Specification and API JAR

⇑ JAXB (Java Architecture for XML Binding) API Specification

⇑⇑ FAQ for jaxb-*.jar - Java Architecture for XML Binding