1 /*
2 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
3 *
4 * This code is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License version 2 only, as
6 * published by the Free Software Foundation. Oracle designates this
7 * particular file as subject to the "Classpath" exception as provided
8 * by Oracle in the LICENSE file that accompanied this code.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
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23 */
24
25 /*
26 * This file is available under and governed by the GNU General Public
27 * License version 2 only, as published by the Free Software Foundation.
28 * However, the following notice accompanied the original version of this
29 * file and, per its terms, should not be removed:
30 *
31 * Copyright (c) 2004 World Wide Web Consortium,
32 *
33 * (Massachusetts Institute of Technology, European Research Consortium for
34 * Informatics and Mathematics, Keio University). All Rights Reserved. This
35 * work is distributed under the W3C(r) Software License [1] in the hope that
36 * it will be useful, but WITHOUT ANY WARRANTY; without even the implied
37 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
38 *
39 * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231
40 */
41
42 package org.w3c.dom;
43
44 /**
45 * The <code>Attr</code> interface represents an attribute in an
46 * <code>Element</code> object. Typically the allowable values for the
47 * attribute are defined in a schema associated with the document.
48 * <p><code>Attr</code> objects inherit the <code>Node</code> interface, but
49 * since they are not actually child nodes of the element they describe, the
50 * DOM does not consider them part of the document tree. Thus, the
51 * <code>Node</code> attributes <code>parentNode</code>,
52 * <code>previousSibling</code>, and <code>nextSibling</code> have a
53 * <code>null</code> value for <code>Attr</code> objects. The DOM takes the
54 * view that attributes are properties of elements rather than having a
55 * separate identity from the elements they are associated with; this should
56 * make it more efficient to implement such features as default attributes
57 * associated with all elements of a given type. Furthermore,
58 * <code>Attr</code> nodes may not be immediate children of a
59 * <code>DocumentFragment</code>. However, they can be associated with
60 * <code>Element</code> nodes contained within a
61 * <code>DocumentFragment</code>. In short, users and implementors of the
62 * DOM need to be aware that <code>Attr</code> nodes have some things in
63 * common with other objects inheriting the <code>Node</code> interface, but
64 * they also are quite distinct.
65 * <p>The attribute's effective value is determined as follows: if this
66 * attribute has been explicitly assigned any value, that value is the
67 * attribute's effective value; otherwise, if there is a declaration for
68 * this attribute, and that declaration includes a default value, then that
69 * default value is the attribute's effective value; otherwise, the
70 * attribute does not exist on this element in the structure model until it
71 * has been explicitly added. Note that the <code>Node.nodeValue</code>
72 * attribute on the <code>Attr</code> instance can also be used to retrieve
73 * the string version of the attribute's value(s).
74 * <p> If the attribute was not explicitly given a value in the instance
75 * document but has a default value provided by the schema associated with
76 * the document, an attribute node will be created with
77 * <code>specified</code> set to <code>false</code>. Removing attribute
78 * nodes for which a default value is defined in the schema generates a new
79 * attribute node with the default value and <code>specified</code> set to
80 * <code>false</code>. If validation occurred while invoking
81 * <code>Document.normalizeDocument()</code>, attribute nodes with
82 * <code>specified</code> equals to <code>false</code> are recomputed
83 * according to the default attribute values provided by the schema. If no
84 * default value is associate with this attribute in the schema, the
85 * attribute node is discarded.
86 * <p>In XML, where the value of an attribute can contain entity references,
87 * the child nodes of the <code>Attr</code> node may be either
88 * <code>Text</code> or <code>EntityReference</code> nodes (when these are
89 * in use; see the description of <code>EntityReference</code> for
90 * discussion).
91 * <p>The DOM Core represents all attribute values as simple strings, even if
92 * the DTD or schema associated with the document declares them of some
93 * specific type such as tokenized.
94 * <p>The way attribute value normalization is performed by the DOM
95 * implementation depends on how much the implementation knows about the
96 * schema in use. Typically, the <code>value</code> and
97 * <code>nodeValue</code> attributes of an <code>Attr</code> node initially
98 * returns the normalized value given by the parser. It is also the case
99 * after <code>Document.normalizeDocument()</code> is called (assuming the
100 * right options have been set). But this may not be the case after
101 * mutation, independently of whether the mutation is performed by setting
102 * the string value directly or by changing the <code>Attr</code> child
103 * nodes. In particular, this is true when <a href='http://www.w3.org/TR/2004/REC-xml-20040204#dt-charref'>character
104 * references</a> are involved, given that they are not represented in the DOM and they
105 * impact attribute value normalization. On the other hand, if the
106 * implementation knows about the schema in use when the attribute value is
107 * changed, and it is of a different type than CDATA, it may normalize it
108 * again at that time. This is especially true of specialized DOM
109 * implementations, such as SVG DOM implementations, which store attribute
110 * values in an internal form different from a string.
111 * <p>The following table gives some examples of the relations between the
112 * attribute value in the original document (parsed attribute), the value as
113 * exposed in the DOM, and the serialization of the value:
114 * <table class="striped">
115 * <caption>Examples of the Original, Normalized and Serialized Values </caption>
116 * <thead>
117 * <tr>
118 * <th scope="col">Examples</th>
119 * <th scope="col">Parsed
120 * attribute value</th>
121 * <th scope="col">Initial <code>Attr.value</code></th>
122 * <th scope="col">Serialized attribute value</th>
123 * </tr>
124 * </thead>
125 * <tbody>
126 * <tr>
127 * <th scope="row" valign='top' rowspan='1' colspan='1'>
128 * Character reference</th>
129 * <td valign='top' rowspan='1' colspan='1'>
130 * <pre>"x&#178;=5"</pre>
131 * </td>
132 * <td valign='top' rowspan='1' colspan='1'>
133 * <pre>"x²=5"</pre>
134 * </td>
135 * <td valign='top' rowspan='1' colspan='1'>
136 * <pre>"x&#178;=5"</pre>
137 * </td>
138 * </tr>
139 * <tr>
140 * <th scope="row" valign='top' rowspan='1' colspan='1'>Built-in
141 * character entity</th>
142 * <td valign='top' rowspan='1' colspan='1'>
143 * <pre>"y&lt;6"</pre>
144 * </td>
145 * <td valign='top' rowspan='1' colspan='1'>
146 * <pre>"y<6"</pre>
147 * </td>
148 * <td valign='top' rowspan='1' colspan='1'>
149 * <pre>"y&lt;6"</pre>
150 * </td>
151 * </tr>
152 * <tr>
153 * <th scope="row" valign='top' rowspan='1' colspan='1'>Literal newline between</th>
154 * <td valign='top' rowspan='1' colspan='1'>
155 * <pre>
156 * "x=5&#10;y=6"</pre>
157 * </td>
158 * <td valign='top' rowspan='1' colspan='1'>
159 * <pre>"x=5 y=6"</pre>
160 * </td>
161 * <td valign='top' rowspan='1' colspan='1'>
162 * <pre>"x=5&#10;y=6"</pre>
163 * </td>
164 * </tr>
165 * <tr>
166 * <th scope="row" valign='top' rowspan='1' colspan='1'>Normalized newline between</th>
167 * <td valign='top' rowspan='1' colspan='1'>
168 * <pre>"x=5
169 * y=6"</pre>
170 * </td>
171 * <td valign='top' rowspan='1' colspan='1'>
172 * <pre>"x=5 y=6"</pre>
173 * </td>
174 * <td valign='top' rowspan='1' colspan='1'>
175 * <pre>"x=5 y=6"</pre>
176 * </td>
177 * </tr>
178 * <tr>
179 * <th scope="row" valign='top' rowspan='1' colspan='1'>Entity <code>e</code> with literal newline</th>
180 * <td valign='top' rowspan='1' colspan='1'>
181 * <pre>
182 * <!ENTITY e '...&#10;...'> [...]> "x=5&e;y=6"</pre>
183 * </td>
184 * <td valign='top' rowspan='1' colspan='1'><em>Dependent on Implementation and Load Options</em></td>
185 * <td valign='top' rowspan='1' colspan='1'><em>Dependent on Implementation and Load/Save Options</em></td>
186 * </tr>
187 * </tbody>
188 * </table>
189 * <p>See also the <a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407'>Document Object Model (DOM) Level 3 Core Specification</a>.
190 */
191 public interface Attr extends Node {
192 /**
193 * Returns the name of this attribute. If <code>Node.localName</code> is
194 * different from <code>null</code>, this attribute is a qualified name.
195 */
196 public String getName();
197
198 /**
199 * <code>True</code> if this attribute was explicitly given a value in
200 * the instance document, <code>false</code> otherwise. If the
201 * application changed the value of this attribute node (even if it ends
202 * up having the same value as the default value) then it is set to
203 * <code>true</code>. The implementation may handle attributes with
204 * default values from other schemas similarly but applications should
205 * use <code>Document.normalizeDocument()</code> to guarantee this
206 * information is up-to-date.
207 */
208 public boolean getSpecified();
209
210 /**
211 * On retrieval, the value of the attribute is returned as a string.
212 * Character and general entity references are replaced with their
213 * values. See also the method <code>getAttribute</code> on the
214 * <code>Element</code> interface.
215 * <br>On setting, this creates a <code>Text</code> node with the unparsed
216 * contents of the string, i.e. any characters that an XML processor
217 * would recognize as markup are instead treated as literal text. See
218 * also the method <code>Element.setAttribute()</code>.
219 * <br> Some specialized implementations, such as some [<a href='http://www.w3.org/TR/2003/REC-SVG11-20030114/'>SVG 1.1</a>]
220 * implementations, may do normalization automatically, even after
221 * mutation; in such case, the value on retrieval may differ from the
222 * value on setting.
223 */
224 public String getValue();
225 /**
226 * On retrieval, the value of the attribute is returned as a string.
227 * Character and general entity references are replaced with their
228 * values. See also the method <code>getAttribute</code> on the
229 * <code>Element</code> interface.
230 * <br>On setting, this creates a <code>Text</code> node with the unparsed
231 * contents of the string, i.e. any characters that an XML processor
232 * would recognize as markup are instead treated as literal text. See
233 * also the method <code>Element.setAttribute()</code>.
234 * <br> Some specialized implementations, such as some [<a href='http://www.w3.org/TR/2003/REC-SVG11-20030114/'>SVG 1.1</a>]
235 * implementations, may do normalization automatically, even after
236 * mutation; in such case, the value on retrieval may differ from the
237 * value on setting.
238 * @exception DOMException
239 * NO_MODIFICATION_ALLOWED_ERR: Raised when the node is readonly.
240 */
241 public void setValue(String value)
242 throws DOMException;
243
244 /**
245 * The <code>Element</code> node this attribute is attached to or
246 * <code>null</code> if this attribute is not in use.
247 * @since 1.4, DOM Level 2
248 */
249 public Element getOwnerElement();
250
251 /**
252 * The type information associated with this attribute. While the type
253 * information contained in this attribute is guarantee to be correct
254 * after loading the document or invoking
255 * <code>Document.normalizeDocument()</code>, <code>schemaTypeInfo</code>
256 * may not be reliable if the node was moved.
257 * @since 1.5, DOM Level 3
258 */
259 public TypeInfo getSchemaTypeInfo();
260
261 /**
262 * Returns whether this attribute is known to be of type ID (i.e. to
263 * contain an identifier for its owner element) or not. When it is and
264 * its value is unique, the <code>ownerElement</code> of this attribute
265 * can be retrieved using the method <code>Document.getElementById</code>
266 * . The implementation could use several ways to determine if an
267 * attribute node is known to contain an identifier:
268 * <ul>
269 * <li> If validation
270 * occurred using an XML Schema [<a href='http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/'>XML Schema Part 1</a>]
271 * while loading the document or while invoking
272 * <code>Document.normalizeDocument()</code>, the post-schema-validation
273 * infoset contributions (PSVI contributions) values are used to
274 * determine if this attribute is a schema-determined ID attribute using
275 * the <a href='http://www.w3.org/TR/2003/REC-xptr-framework-20030325/#term-sdi'>
276 * schema-determined ID</a> definition in [<a href='http://www.w3.org/TR/2003/REC-xptr-framework-20030325/'>XPointer</a>]
277 * .
278 * </li>
279 * <li> If validation occurred using a DTD while loading the document or
280 * while invoking <code>Document.normalizeDocument()</code>, the infoset <b>[type definition]</b> value is used to determine if this attribute is a DTD-determined ID
281 * attribute using the <a href='http://www.w3.org/TR/2003/REC-xptr-framework-20030325/#term-ddi'>
282 * DTD-determined ID</a> definition in [<a href='http://www.w3.org/TR/2003/REC-xptr-framework-20030325/'>XPointer</a>]
283 * .
284 * </li>
285 * <li> from the use of the methods <code>Element.setIdAttribute()</code>,
286 * <code>Element.setIdAttributeNS()</code>, or
287 * <code>Element.setIdAttributeNode()</code>, i.e. it is an
288 * user-determined ID attribute;
289 * <p ><b>Note:</b> XPointer framework (see section 3.2 in [<a href='http://www.w3.org/TR/2003/REC-xptr-framework-20030325/'>XPointer</a>]
290 * ) consider the DOM user-determined ID attribute as being part of the
291 * XPointer externally-determined ID definition.
292 * </li>
293 * <li> using mechanisms that
294 * are outside the scope of this specification, it is then an
295 * externally-determined ID attribute. This includes using schema
296 * languages different from XML schema and DTD.
297 * </li>
298 * </ul>
299 * <br> If validation occurred while invoking
300 * <code>Document.normalizeDocument()</code>, all user-determined ID
301 * attributes are reset and all attribute nodes ID information are then
302 * reevaluated in accordance to the schema used. As a consequence, if
303 * the <code>Attr.schemaTypeInfo</code> attribute contains an ID type,
304 * <code>isId</code> will always return true.
305 * @since 1.5, DOM Level 3
306 */
307 public boolean isId();
308
309 }