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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

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 * accompanied this code).

 *

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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>&#64;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;

        }

    }

}