1 package org.jaxen.util;
2
3 /*
4 * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/util/DescendantAxisIterator.java,v 1.11 2005/07/24 11:51:14 elharo Exp $
5 * $Revision: 1.11 $
6 * $Date: 2005/07/24 11:51:14 $
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: DescendantAxisIterator.java,v 1.11 2005/07/24 11:51:14 elharo Exp $
62 */
63
64 import org.jaxen.Navigator;
65 import org.jaxen.UnsupportedAxisException;
66 import org.jaxen.JaxenRuntimeException;
67
68 import java.util.Iterator;
69 import java.util.NoSuchElementException;
70 import java.util.ArrayList;
71
72 public class DescendantAxisIterator implements Iterator
73 {
74
75 private ArrayList stack = new ArrayList();
76 private Iterator children;
77 private Navigator navigator;
78
79 public DescendantAxisIterator(Object contextNode,
80 Navigator navigator) throws UnsupportedAxisException
81 {
82 this(navigator, navigator.getChildAxisIterator(contextNode));
83 }
84
85 public DescendantAxisIterator(Navigator navigator,
86 Iterator iterator)
87 {
88 this.navigator = navigator;
89 this.children = iterator;
90 }
91
92 public boolean hasNext()
93 {
94 while (!children.hasNext())
95 {
96 if (stack.isEmpty())
97 {
98 return false;
99 }
100 children = (Iterator) stack.remove(stack.size()-1);
101 }
102 return true;
103 }
104
105 public Object next()
106 {
107 try
108 {
109 if (hasNext())
110 {
111 Object node = children.next();
112 stack.add(children);
113 children = navigator.getChildAxisIterator(node);
114 return node;
115 }
116 throw new NoSuchElementException();
117 }
118 catch (UnsupportedAxisException e)
119 {
120 throw new JaxenRuntimeException(e);
121 }
122 }
123
124 public void remove()
125 {
126 throw new UnsupportedOperationException();
127 }
128
129 }