1 /* This file is part of the project "Hilbert II" - http://www.qedeq.org" target="alexandria_uri">http://www.qedeq.org
2 *
3 * Copyright 2000-2014, Michael Meyling <mime@qedeq.org>.
4 *
5 * "Hilbert II" is free software; you can redistribute
6 * it and/or modify it under the terms of the GNU General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 */
15
16 package org.qedeq.kernel.se.visitor;
17
18 import org.qedeq.kernel.se.base.list.Atom;
19 import org.qedeq.kernel.se.base.list.ElementList;
20 import org.qedeq.kernel.se.common.ModuleDataException;
21
22
23 /**
24 * Visit elements of the list package.
25 *
26 * @author Michael Meyling
27 */
28 public interface ListVisitor {
29
30 /**
31 * Visit certain element. Begin of visit.
32 *
33 * @param atom Begin visit of this element.
34 * @throws ModuleDataException Major problem occurred.
35 */
36 public void visitEnter(Atom atom) throws ModuleDataException;
37
38 /**
39 * Visit certain element. Begin of visit.
40 *
41 * @param list Begin visit of this element.
42 * @throws ModuleDataException Major problem occurred.
43 */
44 public void visitEnter(ElementList list) throws ModuleDataException;
45
46 /**
47 * Visit certain element. End of visit.
48 *
49 * @param atom End visit of this element.
50 * @throws ModuleDataException Major problem occurred.
51 */
52 public void visitLeave(Atom atom) throws ModuleDataException;
53
54 /**
55 * Visit certain element. End of visit.
56 *
57 * @param list End visit of this element.
58 * @throws ModuleDataException Major problem occurred.
59 */
60 public void visitLeave(ElementList list) throws ModuleDataException;
61
62 }