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/DomHandler.java

/*
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 *
 * Copyright (c) 2005-2017 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
 * 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
 * only if the new code is made subject to such option by the copyright
 * holder.
 */

package javax.xml.bind.annotation;

import javax.xml.bind.ValidationEventHandler;
import javax.xml.transform.Result;
import javax.xml.transform.Source;

/**
 * Converts an element (and its descendants)
 * from/to DOM (or similar) representation.
 *
 * <p>
 * Implementations of this interface will be used in conjunction with
 * {@link XmlAnyElement} annotation to map an element of XML into a representation
 * of infoset such as W3C DOM.
 *
 * <p>
 * Implementations hide how a portion of XML is converted into/from such
 * DOM-like representation, allowing JAXB providers to work with arbitrary
 * such library.
 *
 * <P>
 * This interface is intended to be implemented by library writers
 * and consumed by JAXB providers. None of those methods are intended to
 * be called from applications.
 *
 * @author Kohsuke Kawaguchi
 * @since 1.6, JAXB 2.0
 */
public interface DomHandler<ElementT,ResultT extends Result> {
    /**
     * When a JAXB provider needs to unmarshal a part of a document into an
     * infoset representation, it first calls this method to create a
     * {@link Result} object.
     *
     * <p>
     * A JAXB provider will then send a portion of the XML
     * into the given result. Such a portion always form a subtree
     * of the whole XML document rooted at an element.
     *
     * @param errorHandler
     *      if any error happens between the invocation of this method
     *      and the invocation of {@link #getElement(Result)}, they
     *      must be reported to this handler.
     *
     *      The caller must provide a non-null error handler.
     *
     *      The {@link Result} object created from this method
     *      may hold a reference to this error handler.
     *
     * @return
     *      null if the operation fails. The error must have been reported
     *      to the error handler.
     */
    ResultT createUnmarshaller( ValidationEventHandler errorHandler );

    /**
     * Once the portion is sent to the {@link Result}. This method is called
     * by a JAXB provider to obtain the unmarshalled element representation.
     *
     * <p>
     * Multiple invocations of this method may return different objects.
     * This method can be invoked only when the whole sub-tree are fed
     * to the {@link Result} object.
     *
     * @param rt
     *      The {@link Result} object created by {@link #createUnmarshaller(ValidationEventHandler)}.
     *
     * @return
     *      null if the operation fails. The error must have been reported
     *      to the error handler.
     */
    ElementT getElement(ResultT rt);

    /**
     * This method is called when a JAXB provider needs to marshal an element
     * to XML.
     *
     * <p>
     * If non-null, the returned {@link Source} must contain a whole document
     * rooted at one element, which will then be weaved into a bigger document
     * that the JAXB provider is marshalling.
     *
     * @param errorHandler
     *      Receives any errors happened during the process of converting
     *      an element into a {@link Source}.
     *
     *      The caller must provide a non-null error handler.
     *
     * @return
     *      null if there was an error. The error should have been reported
     *      to the handler.
     */
    Source marshal( ElementT n, ValidationEventHandler errorHandler );
}

⏎ javax/xml/bind/annotation/DomHandler.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