Java tutorial
/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. * * 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]" * * Contributor(s): * 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; import javax.xml.namespace.QName; /** * Provide access to JAXB xml binding data for a JAXB object. * * <p> * Intially, the intent of this class is to just conceptualize how * a JAXB application developer can access xml binding information, * independent if binding model is java to schema or schema to java. * Since accessing the XML element name related to a JAXB element is * a highly requested feature, demonstrate access to this * binding information. * * The factory method to get a <code>JAXBIntrospector</code> instance is * {@link JAXBContext#createJAXBIntrospector()}. * * @see JAXBContext#createJAXBIntrospector() * @since 1.6, JAXB 2.0 */ public abstract class JAXBIntrospector { /** * <p>Return true if <code>object</code> represents a JAXB element.</p> * <p>Parameter <code>object</code> is a JAXB element for following cases: * <ol> * <li>It is an instance of <code>javax.xml.bind.JAXBElement</code>.</li> * <li>The class of <code>object</code> is annotated with * <code>@XmlRootElement</code>. * </li> * </ol> * * @see #getElementName(Object) */ public abstract boolean isElement(Object object); /** * <p>Get xml element qname for <code>jaxbElement</code>.</p> * * @param jaxbElement is an object that {@link #isElement(Object)} returned true. * * @return xml element qname associated with jaxbElement; * null if <code>jaxbElement</code> is not a JAXB Element. */ public abstract QName getElementName(Object jaxbElement); /** * <p>Get the element value of a JAXB element.</p> * * <p>Convenience method to abstract whether working with either * a javax.xml.bind.JAXBElement instance or an instance of * {@code @XmlRootElement} annotated Java class.</p> * * @param jaxbElement object that #isElement(Object) returns true. * * @return The element value of the <code>jaxbElement</code>. */ public static Object getValue(Object jaxbElement) { if (jaxbElement instanceof JAXBElement) { return ((JAXBElement) jaxbElement).getValue(); } else { // assume that class of this instance is // annotated with @XmlRootElement. return jaxbElement; } } }