jakarta.xml.bind.JAXBIntrospector Maven / Gradle / Ivy
/*
* Copyright (c) 2004, 2020 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0, which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package jakarta.xml.bind;
import javax.xml.namespace.QName;
/**
* Provide access to JAXB xml binding data for a JAXB object.
*
*
* 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 JAXBIntrospector instance is
* {@link JAXBContext#createJAXBIntrospector()}.
*
* @see JAXBContext#createJAXBIntrospector()
* @since 1.6, JAXB 2.0
*/
public abstract class JAXBIntrospector {
/**
*
Return true if object represents a JAXB element.
* Parameter object is a JAXB element for following cases:
*
* - It is an instance of
jakarta.xml.bind.JAXBElement.
* - The class of
object is annotated with
* @XmlRootElement.
*
*
*
* @see #getElementName(Object)
*/
public abstract boolean isElement(Object object);
/**
* Get xml element qname for jaxbElement.
*
* @param jaxbElement is an object that {@link #isElement(Object)} returned true.
*
* @return xml element qname associated with jaxbElement;
* null if jaxbElement is not a JAXB Element.
*/
public abstract QName getElementName(Object jaxbElement);
/**
* Get the element value of a JAXB element.
*
* Convenience method to abstract whether working with either
* a jakarta.xml.bind.JAXBElement instance or an instance of
* {@code @XmlRootElement} annotated Java class.
*
* @param jaxbElement object that #isElement(Object) returns true.
*
* @return The element value of the jaxbElement.
*/
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;
}
}
}