Classes in this File | Line Coverage | Branch Coverage | Complexity | ||||
ConfigurationNodeIteratorBase |
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| 1.3636363636363635;1,364 |
1 | /* | |
2 | * Licensed to the Apache Software Foundation (ASF) under one or more | |
3 | * contributor license agreements. See the NOTICE file distributed with | |
4 | * this work for additional information regarding copyright ownership. | |
5 | * The ASF licenses this file to You under the Apache License, Version 2.0 | |
6 | * (the "License"); you may not use this file except in compliance with | |
7 | * the License. You may obtain a copy of the License at | |
8 | * | |
9 | * http://www.apache.org/licenses/LICENSE-2.0 | |
10 | * | |
11 | * Unless required by applicable law or agreed to in writing, software | |
12 | * distributed under the License is distributed on an "AS IS" BASIS, | |
13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | |
14 | * See the License for the specific language governing permissions and | |
15 | * limitations under the License. | |
16 | */ | |
17 | package org.apache.commons.configuration.tree.xpath; | |
18 | ||
19 | import java.util.List; | |
20 | ||
21 | import org.apache.commons.configuration.tree.ConfigurationNode; | |
22 | import org.apache.commons.jxpath.ri.model.NodeIterator; | |
23 | import org.apache.commons.jxpath.ri.model.NodePointer; | |
24 | ||
25 | /** | |
26 | * <p> | |
27 | * A base class for implementing iterators over configuration nodes. | |
28 | * </p> | |
29 | * <p> | |
30 | * This class already provides common functionality for implementing the | |
31 | * iteration process. Derived classes will implement specific behavior based on | |
32 | * the concrete node type (child node or attribute node). | |
33 | * </p> | |
34 | * | |
35 | * @since 1.3 | |
36 | * @author Oliver Heger | |
37 | * @version $Id: ConfigurationNodeIteratorBase.java 439648 2006-09-02 20:42:10Z oheger $ | |
38 | */ | |
39 | abstract class ConfigurationNodeIteratorBase implements NodeIterator | |
40 | { | |
41 | /** Stores the parent node pointer. */ | |
42 | private NodePointer parent; | |
43 | ||
44 | /** Stores the list with the sub nodes. */ | |
45 | private List subNodes; | |
46 | ||
47 | /** Stores the current position. */ | |
48 | private int position; | |
49 | ||
50 | /** Stores the start offset of the iterator. */ | |
51 | private int startOffset; | |
52 | ||
53 | /** Stores the reverse flag. */ | |
54 | private boolean reverse; | |
55 | ||
56 | /** | |
57 | * Creates a new instance of <code>ConfigurationNodeIteratorBase</code> | |
58 | * and initializes it. | |
59 | * | |
60 | * @param parent the parent pointer | |
61 | * @param reverse the reverse flag | |
62 | */ | |
63 | protected ConfigurationNodeIteratorBase(NodePointer parent, boolean reverse) | |
64 | 36948 | { |
65 | 36948 | this.parent = parent; |
66 | 36948 | this.reverse = reverse; |
67 | 36948 | } |
68 | ||
69 | /** | |
70 | * Returns the position of the iteration. | |
71 | * | |
72 | * @return the position | |
73 | */ | |
74 | public int getPosition() | |
75 | { | |
76 | 160448 | return position; |
77 | } | |
78 | ||
79 | /** | |
80 | * Sets the position of the iteration. | |
81 | * | |
82 | * @param pos the new position | |
83 | * @return a flag if this is a valid position | |
84 | */ | |
85 | public boolean setPosition(int pos) | |
86 | { | |
87 | 89532 | position = pos; |
88 | 89532 | return pos >= 1 && pos <= getMaxPosition(); |
89 | } | |
90 | ||
91 | /** | |
92 | * Returns the current node pointer. | |
93 | * | |
94 | * @return the current pointer in this iteration | |
95 | */ | |
96 | public NodePointer getNodePointer() | |
97 | { | |
98 | 73191 | if (getPosition() < 1 && !setPosition(1)) |
99 | { | |
100 | 1 | return null; |
101 | } | |
102 | ||
103 | 73190 | return createNodePointer((ConfigurationNode) subNodes |
104 | .get(positionToIndex(getPosition()))); | |
105 | } | |
106 | ||
107 | /** | |
108 | * Returns the parent node pointer. | |
109 | * | |
110 | * @return the parent node pointer | |
111 | */ | |
112 | protected NodePointer getParent() | |
113 | { | |
114 | 73190 | return parent; |
115 | } | |
116 | ||
117 | /** | |
118 | * Returns the start offset of the iteration. | |
119 | * | |
120 | * @return the start offset | |
121 | */ | |
122 | protected int getStartOffset() | |
123 | { | |
124 | 162722 | return startOffset; |
125 | } | |
126 | ||
127 | /** | |
128 | * Sets the start offset of the iteration. This is used when a start element | |
129 | * was set. | |
130 | * | |
131 | * @param startOffset the start offset | |
132 | */ | |
133 | protected void setStartOffset(int startOffset) | |
134 | { | |
135 | 8 | this.startOffset = startOffset; |
136 | 8 | if (reverse) |
137 | { | |
138 | 5 | this.startOffset--; |
139 | } | |
140 | else | |
141 | { | |
142 | 3 | this.startOffset++; |
143 | } | |
144 | 8 | } |
145 | ||
146 | /** | |
147 | * Initializes the list of sub nodes for the iteration. This method must be | |
148 | * called during initialization phase. | |
149 | * | |
150 | * @param nodes the list with the sub nodes | |
151 | */ | |
152 | protected void initSubNodeList(List nodes) | |
153 | { | |
154 | 36948 | subNodes = nodes; |
155 | 36948 | if (reverse) |
156 | { | |
157 | 3 | setStartOffset(subNodes.size()); |
158 | } | |
159 | 36948 | } |
160 | ||
161 | /** | |
162 | * Returns the maximum position for this iterator. | |
163 | * | |
164 | * @return the maximum allowed position | |
165 | */ | |
166 | protected int getMaxPosition() | |
167 | { | |
168 | 89532 | return reverse ? getStartOffset() + 1 : subNodes.size() |
169 | - getStartOffset(); | |
170 | } | |
171 | ||
172 | /** | |
173 | * Creates the configuration node pointer for the current position. This | |
174 | * method is called by <code>getNodePointer()</code>. Derived classes | |
175 | * must create the correct pointer object. | |
176 | * | |
177 | * @param node the current configuration node | |
178 | * @return the node pointer | |
179 | */ | |
180 | protected NodePointer createNodePointer(ConfigurationNode node) | |
181 | { | |
182 | 73190 | return new ConfigurationNodePointer(getParent(), node); |
183 | } | |
184 | ||
185 | /** | |
186 | * Returns the index in the data list for the given position. This method | |
187 | * also checks the reverse flag. | |
188 | * | |
189 | * @param pos the position (1-based) | |
190 | * @return the corresponding list index | |
191 | */ | |
192 | protected int positionToIndex(int pos) | |
193 | { | |
194 | 73190 | return (reverse ? 1 - pos : pos - 1) + getStartOffset(); |
195 | } | |
196 | } |