1 package org.jaxen;
2
3 /*
4 * $Header: $
5 * $Revision: $
6 * $Date: $
7 *
8 * ====================================================================
9 *
10 * Copyright (C) 2000-2005 bob mcwhirter & James Strachan.
11 * All rights reserved.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 *
17 * 1. Redistributions of source code must retain the above copyright
18 * notice, this list of conditions, and the following disclaimer.
19 *
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions, and the disclaimer that follows
22 * these conditions in the documentation and/or other materials
23 * provided with the distribution.
24 *
25 * 3. The name "Jaxen" must not be used to endorse or promote products
26 * derived from this software without prior written permission. For
27 * written permission, please contact license@jaxen.org.
28 *
29 * 4. Products derived from this software may not be called "Jaxen", nor
30 * may "Jaxen" appear in their name, without prior written permission
31 * from the Jaxen Project Management (pm@jaxen.org).
32 *
33 * In addition, we request (but do not require) that you include in the
34 * end-user documentation provided with the redistribution and/or in the
35 * software itself an acknowledgement equivalent to the following:
36 * "This product includes software developed by the
37 * Jaxen Project <http://www.jaxen.org/>."
38 * Alternatively, the acknowledgment may be graphical using the logos
39 * available at http://www.jaxen.org/
40 *
41 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
42 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
43 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
44 * DISCLAIMED. IN NO EVENT SHALL THE Jaxen AUTHORS OR THE PROJECT
45 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
46 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
47 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
48 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
49 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
50 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
51 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * SUCH DAMAGE.
53 *
54 * ====================================================================
55 * This software consists of voluntary contributions made by many
56 * individuals on behalf of the Jaxen Project and was originally
57 * created by bob mcwhirter <bob@werken.com> and
58 * James Strachan <jstrachan@apache.org>. For more information on the
59 * Jaxen Project, please see <http://www.jaxen.org/>.
60 *
61 * $Id: $
62 */
63
64 import java.util.Collections;
65 import java.util.Iterator;
66 import java.util.ListIterator;
67
68 /***
69 * Thread-safe constant iterators used to avoid the overhead of creating
70 * empty lists.
71 */
72 public class JaxenConstants
73 {
74
75 private JaxenConstants() {}
76
77 /***
78 * An iterator with no elements. <code>hasNext()</code> always
79 * returns false. This is thread-safe.
80 */
81 public static final Iterator EMPTY_ITERATOR = Collections.EMPTY_LIST.iterator();
82
83 /***
84 * A list iterator with no elements. <code>hasNext()</code> always
85 * returns false. This is thread-safe.
86 */
87 public static final ListIterator EMPTY_LIST_ITERATOR = Collections.EMPTY_LIST.listIterator();
88
89 }