001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the "License");
007 * you may not use this file except in compliance with the License.
008 * You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 /*
019 * $Id: DTMNamedNodeMap.java 1225427 2011-12-29 04:33:32Z mrglavas $
020 */
021 package org.apache.xml.dtm.ref;
022
023 import org.apache.xml.dtm.DTM;
024
025 import org.w3c.dom.DOMException;
026 import org.w3c.dom.NamedNodeMap;
027 import org.w3c.dom.Node;
028
029 /**
030 * DTMNamedNodeMap is a quickie (as opposed to quick) implementation of the DOM's
031 * NamedNodeMap interface, intended to support DTMProxy's getAttributes()
032 * call.
033 * <p>
034 * ***** Note: this does _not_ current attempt to cache any of the data;
035 * if you ask for attribute 27 and then 28, you'll have to rescan the first
036 * 27. It should probably at least keep track of the last one retrieved,
037 * and possibly buffer the whole array.
038 * <p>
039 * ***** Also note that there's no fastpath for the by-name query; we search
040 * linearly until we find it or fail to find it. Again, that could be
041 * optimized at some cost in object creation/storage.
042 * @xsl.usage internal
043 */
044 public class DTMNamedNodeMap implements NamedNodeMap
045 {
046
047 /** The DTM for this node. */
048 DTM dtm;
049
050 /** The DTM element handle. */
051 int element;
052
053 /** The number of nodes in this map. */
054 short m_count = -1;
055
056 /**
057 * Create a getAttributes NamedNodeMap for a given DTM element node
058 *
059 * @param dtm The DTM Reference, must be non-null.
060 * @param element The DTM element handle.
061 */
062 public DTMNamedNodeMap(DTM dtm, int element)
063 {
064 this.dtm = dtm;
065 this.element = element;
066 }
067
068 /**
069 * Return the number of Attributes on this Element
070 *
071 * @return The number of nodes in this map.
072 */
073 public int getLength()
074 {
075
076 if (m_count == -1)
077 {
078 short count = 0;
079
080 for (int n = dtm.getFirstAttribute(element); n != -1;
081 n = dtm.getNextAttribute(n))
082 {
083 ++count;
084 }
085
086 m_count = count;
087 }
088
089 return (int) m_count;
090 }
091
092 /**
093 * Retrieves a node specified by name.
094 * @param name The <code>nodeName</code> of a node to retrieve.
095 * @return A <code>Node</code> (of any type) with the specified
096 * <code>nodeName</code>, or <code>null</code> if it does not identify
097 * any node in this map.
098 */
099 public Node getNamedItem(String name)
100 {
101
102 for (int n = dtm.getFirstAttribute(element); n != DTM.NULL;
103 n = dtm.getNextAttribute(n))
104 {
105 if (dtm.getNodeName(n).equals(name))
106 return dtm.getNode(n);
107 }
108
109 return null;
110 }
111
112 /**
113 * Returns the <code>index</code>th item in the map. If <code>index</code>
114 * is greater than or equal to the number of nodes in this map, this
115 * returns <code>null</code>.
116 * @param i The index of the requested item.
117 * @return The node at the <code>index</code>th position in the map, or
118 * <code>null</code> if that is not a valid index.
119 */
120 public Node item(int i)
121 {
122
123 int count = 0;
124
125 for (int n = dtm.getFirstAttribute(element); n != -1;
126 n = dtm.getNextAttribute(n))
127 {
128 if (count == i)
129 return dtm.getNode(n);
130 else
131 ++count;
132 }
133
134 return null;
135 }
136
137 /**
138 * Adds a node using its <code>nodeName</code> attribute. If a node with
139 * that name is already present in this map, it is replaced by the new
140 * one.
141 * <br>As the <code>nodeName</code> attribute is used to derive the name
142 * which the node must be stored under, multiple nodes of certain types
143 * (those that have a "special" string value) cannot be stored as the
144 * names would clash. This is seen as preferable to allowing nodes to be
145 * aliased.
146 * @param newNode node to store in this map. The node will later be
147 * accessible using the value of its <code>nodeName</code> attribute.
148 *
149 * @return If the new <code>Node</code> replaces an existing node the
150 * replaced <code>Node</code> is returned, otherwise <code>null</code>
151 * is returned.
152 * @exception DOMException
153 * WRONG_DOCUMENT_ERR: Raised if <code>arg</code> was created from a
154 * different document than the one that created this map.
155 * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this map is readonly.
156 * <br>INUSE_ATTRIBUTE_ERR: Raised if <code>arg</code> is an
157 * <code>Attr</code> that is already an attribute of another
158 * <code>Element</code> object. The DOM user must explicitly clone
159 * <code>Attr</code> nodes to re-use them in other elements.
160 */
161 public Node setNamedItem(Node newNode)
162 {
163 throw new DTMException(DTMException.NO_MODIFICATION_ALLOWED_ERR);
164 }
165
166 /**
167 * Removes a node specified by name. When this map contains the attributes
168 * attached to an element, if the removed attribute is known to have a
169 * default value, an attribute immediately appears containing the
170 * default value as well as the corresponding namespace URI, local name,
171 * and prefix when applicable.
172 * @param name The <code>nodeName</code> of the node to remove.
173 *
174 * @return The node removed from this map if a node with such a name
175 * exists.
176 * @exception DOMException
177 * NOT_FOUND_ERR: Raised if there is no node named <code>name</code> in
178 * this map.
179 * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this map is readonly.
180 */
181 public Node removeNamedItem(String name)
182 {
183 throw new DTMException(DTMException.NO_MODIFICATION_ALLOWED_ERR);
184 }
185
186 /**
187 * Retrieves a node specified by local name and namespace URI. HTML-only
188 * DOM implementations do not need to implement this method.
189 * @param namespaceURI The namespace URI of the node to retrieve.
190 * @param localName The local name of the node to retrieve.
191 *
192 * @return A <code>Node</code> (of any type) with the specified local
193 * name and namespace URI, or <code>null</code> if they do not
194 * identify any node in this map.
195 * @since DOM Level 2
196 */
197 public Node getNamedItemNS(String namespaceURI, String localName)
198 {
199 Node retNode = null;
200 for (int n = dtm.getFirstAttribute(element); n != DTM.NULL;
201 n = dtm.getNextAttribute(n))
202 {
203 if (localName.equals(dtm.getLocalName(n)))
204 {
205 String nsURI = dtm.getNamespaceURI(n);
206 if ((namespaceURI == null && nsURI == null)
207 || (namespaceURI != null && namespaceURI.equals(nsURI)))
208 {
209 retNode = dtm.getNode(n);
210 break;
211 }
212 }
213 }
214 return retNode;
215 }
216
217 /**
218 * Adds a node using its <code>namespaceURI</code> and
219 * <code>localName</code>. If a node with that namespace URI and that
220 * local name is already present in this map, it is replaced by the new
221 * one.
222 * <br>HTML-only DOM implementations do not need to implement this method.
223 * @param arg A node to store in this map. The node will later be
224 * accessible using the value of its <code>namespaceURI</code> and
225 * <code>localName</code> attributes.
226 *
227 * @return If the new <code>Node</code> replaces an existing node the
228 * replaced <code>Node</code> is returned, otherwise <code>null</code>
229 * is returned.
230 * @exception DOMException
231 * WRONG_DOCUMENT_ERR: Raised if <code>arg</code> was created from a
232 * different document than the one that created this map.
233 * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this map is readonly.
234 * <br>INUSE_ATTRIBUTE_ERR: Raised if <code>arg</code> is an
235 * <code>Attr</code> that is already an attribute of another
236 * <code>Element</code> object. The DOM user must explicitly clone
237 * <code>Attr</code> nodes to re-use them in other elements.
238 * @since DOM Level 2
239 */
240 public Node setNamedItemNS(Node arg) throws DOMException
241 {
242 throw new DTMException(DTMException.NO_MODIFICATION_ALLOWED_ERR);
243 }
244
245 /**
246 * Removes a node specified by local name and namespace URI. A removed
247 * attribute may be known to have a default value when this map contains
248 * the attributes attached to an element, as returned by the attributes
249 * attribute of the <code>Node</code> interface. If so, an attribute
250 * immediately appears containing the default value as well as the
251 * corresponding namespace URI, local name, and prefix when applicable.
252 * <br>HTML-only DOM implementations do not need to implement this method.
253 *
254 * @param namespaceURI The namespace URI of the node to remove.
255 * @param localName The local name of the node to remove.
256 *
257 * @return The node removed from this map if a node with such a local
258 * name and namespace URI exists.
259 * @exception DOMException
260 * NOT_FOUND_ERR: Raised if there is no node with the specified
261 * <code>namespaceURI</code> and <code>localName</code> in this map.
262 * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this map is readonly.
263 * @since DOM Level 2
264 */
265 public Node removeNamedItemNS(String namespaceURI, String localName)
266 throws DOMException
267 {
268 throw new DTMException(DTMException.NO_MODIFICATION_ALLOWED_ERR);
269 }
270
271 /**
272 * Simple implementation of DOMException.
273 * @xsl.usage internal
274 */
275 public static class DTMException extends org.w3c.dom.DOMException
276 {
277 static final long serialVersionUID = -8290238117162437678L;
278 /**
279 * Constructs a DOM/DTM exception.
280 *
281 * @param code
282 * @param message
283 */
284 public DTMException(short code, String message)
285 {
286 super(code, message);
287 }
288
289 /**
290 * Constructor DTMException
291 *
292 *
293 * @param code
294 */
295 public DTMException(short code)
296 {
297 super(code, "");
298 }
299 }
300 }