content: /*
   * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved.
   * 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
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package jdkx.lang.model.element;
  
  import jdkx.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 Ah&eacute;
   * @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) {
          super("Unknown element: \"" + e + "\"");
          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;
      }
  }
  