Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
StackedIterator |
|
| 2.0;2 |
1 | /* | |
2 | * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/util/StackedIterator.java,v 1.12 2006/02/05 21:47:40 elharo Exp $ | |
3 | * $Revision: 1.12 $ | |
4 | * $Date: 2006/02/05 21:47:40 $ | |
5 | * | |
6 | * ==================================================================== | |
7 | * | |
8 | * Copyright 2000-2002 bob mcwhirter & James Strachan. | |
9 | * All rights reserved. | |
10 | * | |
11 | * Redistribution and use in source and binary forms, with or without | |
12 | * modification, are permitted provided that the following conditions are | |
13 | * met: | |
14 | * | |
15 | * * Redistributions of source code must retain the above copyright | |
16 | * notice, this list of conditions and the following disclaimer. | |
17 | * | |
18 | * * Redistributions in binary form must reproduce the above copyright | |
19 | * notice, this list of conditions and the following disclaimer in the | |
20 | * documentation and/or other materials provided with the distribution. | |
21 | * | |
22 | * * Neither the name of the Jaxen Project nor the names of its | |
23 | * contributors may be used to endorse or promote products derived | |
24 | * from this software without specific prior written permission. | |
25 | * | |
26 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS | |
27 | * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED | |
28 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A | |
29 | * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER | |
30 | * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
31 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |
32 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |
33 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF | |
34 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING | |
35 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS | |
36 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
37 | * | |
38 | * ==================================================================== | |
39 | * This software consists of voluntary contributions made by many | |
40 | * individuals on behalf of the Jaxen Project and was originally | |
41 | * created by bob mcwhirter <bob@werken.com> and | |
42 | * James Strachan <jstrachan@apache.org>. For more information on the | |
43 | * Jaxen Project, please see <http://www.jaxen.org/>. | |
44 | * | |
45 | * $Id: StackedIterator.java,v 1.12 2006/02/05 21:47:40 elharo Exp $ | |
46 | */ | |
47 | ||
48 | ||
49 | ||
50 | package org.jaxen.util; | |
51 | ||
52 | import java.util.HashSet; | |
53 | import java.util.Iterator; | |
54 | import java.util.LinkedList; | |
55 | import java.util.NoSuchElementException; | |
56 | import java.util.Set; | |
57 | ||
58 | import org.jaxen.Navigator; | |
59 | ||
60 | /** | |
61 | * @deprecated this iterator is no longer used to implement any of the Jaxen axes. If you have implemented | |
62 | * a navigator-specific axis based on this class, take a look at the DescendantAxisIterator for ideas | |
63 | * on how to remove that dependency. | |
64 | */ | |
65 | public abstract class StackedIterator implements Iterator | |
66 | { | |
67 | ||
68 | private LinkedList iteratorStack; | |
69 | private Navigator navigator; | |
70 | ||
71 | private Set created; | |
72 | ||
73 | public StackedIterator(Object contextNode, | |
74 | Navigator navigator) | |
75 | 0 | { |
76 | 0 | this.iteratorStack = new LinkedList(); |
77 | 0 | this.created = new HashSet(); |
78 | ||
79 | 0 | init( contextNode, |
80 | navigator ); | |
81 | 0 | } |
82 | ||
83 | protected StackedIterator() | |
84 | 0 | { |
85 | 0 | this.iteratorStack = new LinkedList(); |
86 | 0 | this.created = new HashSet(); |
87 | 0 | } |
88 | ||
89 | protected void init(Object contextNode, | |
90 | Navigator navigator) | |
91 | { | |
92 | 0 | this.navigator = navigator; |
93 | ||
94 | //pushIterator( internalCreateIterator( contextNode ) ); | |
95 | 0 | } |
96 | ||
97 | protected Iterator internalCreateIterator(Object contextNode) | |
98 | { | |
99 | 0 | if ( this.created.contains( contextNode ) ) |
100 | { | |
101 | 0 | return null; |
102 | } | |
103 | ||
104 | 0 | this.created.add( contextNode ); |
105 | ||
106 | 0 | return createIterator( contextNode ); |
107 | } | |
108 | ||
109 | public boolean hasNext() | |
110 | { | |
111 | 0 | Iterator curIter = currentIterator(); |
112 | ||
113 | 0 | if ( curIter == null ) |
114 | { | |
115 | 0 | return false; |
116 | } | |
117 | ||
118 | 0 | return curIter.hasNext(); |
119 | } | |
120 | ||
121 | public Object next() throws NoSuchElementException | |
122 | { | |
123 | 0 | if ( ! hasNext() ) |
124 | { | |
125 | 0 | throw new NoSuchElementException(); |
126 | } | |
127 | ||
128 | 0 | Iterator curIter = currentIterator(); |
129 | 0 | Object object = curIter.next(); |
130 | ||
131 | 0 | pushIterator( internalCreateIterator( object ) ); |
132 | ||
133 | 0 | return object; |
134 | } | |
135 | ||
136 | public void remove() throws UnsupportedOperationException | |
137 | { | |
138 | 0 | throw new UnsupportedOperationException(); |
139 | } | |
140 | ||
141 | abstract protected Iterator createIterator(Object contextNode); | |
142 | ||
143 | protected void pushIterator(Iterator iter) | |
144 | { | |
145 | 0 | if ( iter != null ) |
146 | { | |
147 | 0 | this.iteratorStack.addFirst(iter); //addLast( iter ); |
148 | } | |
149 | 0 | } |
150 | ||
151 | private Iterator currentIterator() | |
152 | { | |
153 | 0 | while ( iteratorStack.size() > 0 ) |
154 | { | |
155 | 0 | Iterator curIter = (Iterator) iteratorStack.getFirst(); |
156 | ||
157 | 0 | if ( curIter.hasNext() ) |
158 | { | |
159 | 0 | return curIter; |
160 | } | |
161 | ||
162 | 0 | iteratorStack.removeFirst(); |
163 | 0 | } |
164 | ||
165 | 0 | return null; |
166 | } | |
167 | ||
168 | protected Navigator getNavigator() | |
169 | { | |
170 | 0 | return this.navigator; |
171 | } | |
172 | } |