##### Coverage Report - org.jaxen.util.PrecedingAxisIterator

Classes in this File | Line Coverage | Branch Coverage | Complexity
PrecedingAxisIterator |
89% |
100% |
| 4.6;4.6

1 |  |
     package org.jaxen.util;
2 |  |
3 |  |
     /*
4 |  |
      * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/util/PrecedingAxisIterator.java,v 1.8 2005/07/24 11:51:14 elharo Exp $
5 |  |
      * $Revision: 1.8 $
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: PrecedingAxisIterator.java,v 1.8 2005/07/24 11:51:14 elharo Exp $
62 |  |
     */
63 |  |
64 |  |
     import org.jaxen.JaxenConstants;
65 |  |
     import org.jaxen.JaxenRuntimeException;
66 |  |
     import org.jaxen.Navigator;
67 |  |
     import org.jaxen.UnsupportedAxisException;
68 |  |
69 |  |
     import java.util.ArrayList;
70 |  |
     import java.util.Iterator;
71 |  |
     import java.util.ListIterator;
72 |  |
     import java.util.NoSuchElementException;
73 |  |
74 |  |
     /**
75 |  |
      * This implementation of 'preceding' works like so:
76 |  |
      * the preceding axis includes preceding-siblings of this node and their
77 |  |
      * descendants. Also, for each ancestor node of this node, it includes
78 |  |
      * all preceding-siblings of that ancestor, and their descendants. Finally, it
79 |  |
      * includes the ancestor nodes themselves.
80 |  |
      * <p/>
81 |  |
      * The reversed descendant-or-self axes that are required are calculated using a
82 |  |
      * stack of reversed 'child-or-self' axes. When asked for a node, it is always taken
83 |  |
      * from a child-or-self axis. If it was the last node on that axis, the node is returned.
84 |  |
      * Otherwise, this axis is pushed on the stack, and the process is repeated with the child-or-self
85 |  |
      * of the node. Eventually this recurses down to the last descendant of any node, then works
86 |  |
      * back up to the root.
87 |  |
      * <p/>
88 |  |
      * I reckon most object models could provide a faster implementation of the reversed
89 |  |
      * 'children-or-self' used here.
90 |  |
      */
91 |  |
     public class PrecedingAxisIterator implements Iterator
92 |  |
     {
93 |  |
         private Iterator ancestorOrSelf;
94 |  |
         private Iterator precedingSibling;
95 |  |
         private ListIterator childrenOrSelf;
96 |  |
         private ArrayList stack;
97 |  |
98 |  |
         private Navigator navigator;
99 |  |
100 |  |
         public PrecedingAxisIterator(Object contextNode,
101 |  |
                                      Navigator navigator) throws UnsupportedAxisException
102 | 474 |
         {
103 | 474 |
             this.navigator = navigator;
104 | 474 |
             this.ancestorOrSelf = navigator.getAncestorOrSelfAxisIterator(contextNode);
105 | 474 |
             this.precedingSibling = JaxenConstants.EMPTY_ITERATOR;
106 | 474 |
             this.childrenOrSelf = JaxenConstants.EMPTY_LIST_ITERATOR;
107 | 474 |
             this.stack = new ArrayList();
108 | 474 |
         }
109 |  |
110 |  |
111 |  |
         public boolean hasNext()
112 |  |
         {
113 |  |
             try
114 |  |
             {
115 | 5352 |
                 while (!childrenOrSelf.hasPrevious())
116 |  |
                 {
117 | 2022 |
                     if (stack.isEmpty())
118 |  |
                     {
119 | 2418 |
                         while (!precedingSibling.hasNext())
120 |  |
                         {
121 | 1866 |
                             if (!ancestorOrSelf.hasNext())
122 |  |
                             {
123 | 468 |
                                 return false;
124 |  |
                             }
125 | 1398 |
                             Object contextNode = ancestorOrSelf.next();
126 | 1398 |
                             precedingSibling = new PrecedingSiblingAxisIterator(contextNode, navigator);
127 |  |
                         }
128 | 552 |
                         Object node = precedingSibling.next();
129 | 552 |
                         childrenOrSelf = childrenOrSelf(node);
130 |  |
                     }
131 |  |
                     else
132 |  |
                     {
133 | 1002 |
                         childrenOrSelf = (ListIterator) stack.remove(stack.size()-1);
134 |  |
                     }
135 |  |
                 }
136 | 3330 |
                 return true;
137 |  |
             }
138 | 0 |
             catch (UnsupportedAxisException e)
139 |  |
             {
140 | 0 |
                 throw new JaxenRuntimeException(e);
141 |  |
             }
142 |  |
         }
143 |  |
144 |  |
         private ListIterator childrenOrSelf(Object node)
145 |  |
         {
146 |  |
             try
147 |  |
             {
148 | 1554 |
                 ArrayList reversed = new ArrayList();
149 | 1554 |
                 reversed.add(node);
150 | 1554 |
                 Iterator childAxisIterator = navigator.getChildAxisIterator(node);
151 | 1554 |
                 if (childAxisIterator != null)
152 |  |
                 {
153 | 2556 |
                     while (childAxisIterator.hasNext())
154 |  |
                     {
155 | 1002 |
                         reversed.add(childAxisIterator.next());
156 |  |
                     }
157 |  |
                 }
158 | 1554 |
                 return reversed.listIterator(reversed.size());
159 |  |
             }
160 | 0 |
             catch (UnsupportedAxisException e)
161 |  |
             {
162 | 0 |
                 throw new JaxenRuntimeException(e);
163 |  |
             }
164 |  |
         }
165 |  |
166 |  |
         public Object next() throws NoSuchElementException
167 |  |
         {
168 | 1560 |
             if (!hasNext())
169 |  |
             {
170 | 6 |
                 throw new NoSuchElementException();
171 |  |
             }
172 |  |
             while (true)
173 |  |
             {
174 | 2556 |
                 Object result = childrenOrSelf.previous();
175 | 2556 |
                 if (childrenOrSelf.hasPrevious())
176 |  |
                 {
177 |  |
                     // if this isn't 'self' construct 'descendant-or-self'
178 | 1002 |
                     stack.add(childrenOrSelf);
179 | 1002 |
                     childrenOrSelf = childrenOrSelf(result);
180 | 1002 |
                     continue;
181 |  |
                 }
182 | 1554 |
                 return result;
183 |  |
             }
184 |  |
         }
185 |  |
186 |  |
187 |  |
         public void remove() throws UnsupportedOperationException
188 |  |
         {
189 | 6 |
             throw new UnsupportedOperationException();
190 |  |
         }
191 |  |
     }