1 /* 2 * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package javax.xml.bind; 27 import javax.xml.namespace.QName; 28 29 /** 30 * Provide access to JAXB xml binding data for a JAXB object. 31 * 32 * <p> 33 * Intially, the intent of this class is to just conceptualize how 34 * a JAXB application developer can access xml binding information, 35 * independent if binding model is java to schema or schema to java. 36 * Since accessing the XML element name related to a JAXB element is 37 * a highly requested feature, demonstrate access to this 38 * binding information. 39 * 40 * The factory method to get a <code>JAXBIntrospector</code> instance is 41 * {@link JAXBContext#createJAXBIntrospector()}. 42 * 43 * @see JAXBContext#createJAXBIntrospector() 44 * @since JAXB2.0 45 */ 46 public abstract class JAXBIntrospector { 47 48 /** 49 * <p>Return true if <code>object</code> represents a JAXB element.</p> 50 * <p>Parameter <code>object</code> is a JAXB element for following cases: 51 * <ol> 52 * <li>It is an instance of <code>javax.xml.bind.JAXBElement</code>.</li> 53 * <li>The class of <code>object</code> is annotated with 54 * <code>@XmlRootElement</code>. 55 * </li> 56 * </ol> 57 * 58 * @see #getElementName(Object) 59 */ 60 public abstract boolean isElement(Object object); 61 62 /** 63 * <p>Get xml element qname for <code>jaxbElement</code>.</p> 64 * 65 * @param jaxbElement is an object that {@link #isElement(Object)} returned true. 66 * 67 * @return xml element qname associated with jaxbElement; 68 * null if <code>jaxbElement</code> is not a JAXB Element. 69 */ 70 public abstract QName getElementName(Object jaxbElement); 71 72 /** 73 * <p>Get the element value of a JAXB element.</p> 74 * 75 * <p>Convenience method to abstract whether working with either 76 * a javax.xml.bind.JAXBElement instance or an instance of 77 * <tt>@XmlRootElement</tt> annotated Java class.</p> 78 * 79 * @param jaxbElement object that #isElement(Object) returns true. 80 * 81 * @return The element value of the <code>jaxbElement</code>. 82 */ 83 public static Object getValue(Object jaxbElement) { 84 if (jaxbElement instanceof JAXBElement) { 85 return ((JAXBElement)jaxbElement).getValue(); 86 } else { 87 // assume that class of this instance is 88 // annotated with @XmlRootElement. 89 return jaxbElement; 90 } 91 } 92 }