/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

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

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

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package javax.lang.model.element;

import javax.lang.model.UnknownEntityException;

/**

 * Indicates that an unknown kind of element was encountered.  This

 * can occur if the language evolves and new kinds of elements are

 * added to the {@code Element} hierarchy.  May be thrown by an

 * {@linkplain ElementVisitor element visitor} to indicate that the

 * visitor was created for a prior version of the language.

 *

 * @author Joseph D. Darcy

 * @author Scott Seligman

 * @author Peter von der Ahé

 * @see ElementVisitor#visitUnknown

 * @since 1.6

 */

public class UnknownElementException extends UnknownEntityException {

    private static final long serialVersionUID = 269L;

    private transient Element element;

    private transient Object parameter;

    /**

     * Creates a new {@code UnknownElementException}.  The {@code p}

     * parameter may be used to pass in an additional argument with

     * information about the context in which the unknown element was

     * encountered; for example, the visit methods of {@link

     * ElementVisitor} may pass in their additional parameter.

     *

     * @param e the unknown element, may be {@code null}

     * @param p an additional parameter, may be {@code null}

     */

    public UnknownElementException(Element e, Object p) {

        element = e;

        this.parameter = p;

    }

    /**

     * Returns the unknown element.

     * The value may be unavailable if this exception has been

     * serialized and then read back in.

     *

     * @return the unknown element, or {@code null} if unavailable

     */

    public Element getUnknownElement() {

        return element;

    }

    /**

     * Returns the additional argument.

     *

     * @return the additional argument, or {@code null} if unavailable

     */

    public Object getArgument() {

        return parameter;

    }

}