1/*
2 * Copyright (c) 2004 World Wide Web Consortium,
3 *
4 * (Massachusetts Institute of Technology, European Research Consortium for
5 * Informatics and Mathematics, Keio University). All Rights Reserved. This
6 * work is distributed under the W3C(r) Software License [1] in the hope that
7 * it will be useful, but WITHOUT ANY WARRANTY; without even the implied
8 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
9 *
10 * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231
11 */
12
13package org.w3c.dom;
14
15/**
16 * The <code>Element</code> interface represents an element in an HTML or XML
17 * document. Elements may have attributes associated with them; since the
18 * <code>Element</code> interface inherits from <code>Node</code>, the
19 * generic <code>Node</code> interface attribute <code>attributes</code> may
20 * be used to retrieve the set of all attributes for an element. There are
21 * methods on the <code>Element</code> interface to retrieve either an
22 * <code>Attr</code> object by name or an attribute value by name. In XML,
23 * where an attribute value may contain entity references, an
24 * <code>Attr</code> object should be retrieved to examine the possibly
25 * fairly complex sub-tree representing the attribute value. On the other
26 * hand, in HTML, where all attributes have simple string values, methods to
27 * directly access an attribute value can safely be used as a convenience.
28 * <p ><b>Note:</b> In DOM Level 2, the method <code>normalize</code> is
29 * inherited from the <code>Node</code> interface where it was moved.
30 * <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>.
31 */
32public interface Element extends Node {
33    /**
34     * The name of the element. If <code>Node.localName</code> is different
35     * from <code>null</code>, this attribute is a qualified name. For
36     * example, in:
37     * <pre> &lt;elementExample id="demo"&gt; ...
38     * &lt;/elementExample&gt; , </pre>
39     *  <code>tagName</code> has the value
40     * <code>"elementExample"</code>. Note that this is case-preserving in
41     * XML, as are all of the operations of the DOM. The HTML DOM returns
42     * the <code>tagName</code> of an HTML element in the canonical
43     * uppercase form, regardless of the case in the source HTML document.
44     */
45    public String getTagName();
46
47    /**
48     * Retrieves an attribute value by name.
49     * @param name The name of the attribute to retrieve.
50     * @return The <code>Attr</code> value as a string, or the empty string
51     *   if that attribute does not have a specified or default value.
52     */
53    public String getAttribute(String name);
54
55    /**
56     * Adds a new attribute. If an attribute with that name is already present
57     * in the element, its value is changed to be that of the value
58     * parameter. This value is a simple string; it is not parsed as it is
59     * being set. So any markup (such as syntax to be recognized as an
60     * entity reference) is treated as literal text, and needs to be
61     * appropriately escaped by the implementation when it is written out.
62     * In order to assign an attribute value that contains entity
63     * references, the user must create an <code>Attr</code> node plus any
64     * <code>Text</code> and <code>EntityReference</code> nodes, build the
65     * appropriate subtree, and use <code>setAttributeNode</code> to assign
66     * it as the value of an attribute.
67     * <br>To set an attribute with a qualified name and namespace URI, use
68     * the <code>setAttributeNS</code> method.
69     * @param name The name of the attribute to create or alter.
70     * @param value Value to set in string form.
71     * @exception DOMException
72     *   INVALID_CHARACTER_ERR: Raised if the specified name is not an XML
73     *   name according to the XML version in use specified in the
74     *   <code>Document.xmlVersion</code> attribute.
75     *   <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
76     */
77    public void setAttribute(String name,
78                             String value)
79                             throws DOMException;
80
81    /**
82     * Removes an attribute by name. If a default value for the removed
83     * attribute is defined in the DTD, a new attribute immediately appears
84     * with the default value as well as the corresponding namespace URI,
85     * local name, and prefix when applicable. The implementation may handle
86     * default values from other schemas similarly but applications should
87     * use <code>Document.normalizeDocument()</code> to guarantee this
88     * information is up-to-date.
89     * <br>If no attribute with this name is found, this method has no effect.
90     * <br>To remove an attribute by local name and namespace URI, use the
91     * <code>removeAttributeNS</code> method.
92     * @param name The name of the attribute to remove.
93     * @exception DOMException
94     *   NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
95     */
96    public void removeAttribute(String name)
97                                throws DOMException;
98
99    /**
100     * Retrieves an attribute node by name.
101     * <br>To retrieve an attribute node by qualified name and namespace URI,
102     * use the <code>getAttributeNodeNS</code> method.
103     * @param name The name (<code>nodeName</code>) of the attribute to
104     *   retrieve.
105     * @return The <code>Attr</code> node with the specified name (
106     *   <code>nodeName</code>) or <code>null</code> if there is no such
107     *   attribute.
108     */
109    public Attr getAttributeNode(String name);
110
111    /**
112     * Adds a new attribute node. If an attribute with that name (
113     * <code>nodeName</code>) is already present in the element, it is
114     * replaced by the new one. Replacing an attribute node by itself has no
115     * effect.
116     * <br>To add a new attribute node with a qualified name and namespace
117     * URI, use the <code>setAttributeNodeNS</code> method.
118     * @param newAttr The <code>Attr</code> node to add to the attribute list.
119     * @return If the <code>newAttr</code> attribute replaces an existing
120     *   attribute, the replaced <code>Attr</code> node is returned,
121     *   otherwise <code>null</code> is returned.
122     * @exception DOMException
123     *   WRONG_DOCUMENT_ERR: Raised if <code>newAttr</code> was created from a
124     *   different document than the one that created the element.
125     *   <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
126     *   <br>INUSE_ATTRIBUTE_ERR: Raised if <code>newAttr</code> is already an
127     *   attribute of another <code>Element</code> object. The DOM user must
128     *   explicitly clone <code>Attr</code> nodes to re-use them in other
129     *   elements.
130     */
131    public Attr setAttributeNode(Attr newAttr)
132                                 throws DOMException;
133
134    /**
135     * Removes the specified attribute node. If a default value for the
136     * removed <code>Attr</code> node is defined in the DTD, a new node
137     * immediately appears with the default value as well as the
138     * corresponding namespace URI, local name, and prefix when applicable.
139     * The implementation may handle default values from other schemas
140     * similarly but applications should use
141     * <code>Document.normalizeDocument()</code> to guarantee this
142     * information is up-to-date.
143     * @param oldAttr The <code>Attr</code> node to remove from the attribute
144     *   list.
145     * @return The <code>Attr</code> node that was removed.
146     * @exception DOMException
147     *   NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
148     *   <br>NOT_FOUND_ERR: Raised if <code>oldAttr</code> is not an attribute
149     *   of the element.
150     */
151    public Attr removeAttributeNode(Attr oldAttr)
152                                    throws DOMException;
153
154    /**
155     * Returns a <code>NodeList</code> of all descendant <code>Elements</code>
156     * with a given tag name, in document order.
157     * @param name The name of the tag to match on. The special value "*"
158     *   matches all tags.
159     * @return A list of matching <code>Element</code> nodes.
160     */
161    public NodeList getElementsByTagName(String name);
162
163    /**
164     * Retrieves an attribute value by local name and namespace URI.
165     * <br>Per [<a href='http://www.w3.org/TR/1999/REC-xml-names-19990114/'>XML Namespaces</a>]
166     * , applications must use the value <code>null</code> as the
167     * <code>namespaceURI</code> parameter for methods if they wish to have
168     * no namespace.
169     * @param namespaceURI The namespace URI of the attribute to retrieve.
170     * @param localName The local name of the attribute to retrieve.
171     * @return The <code>Attr</code> value as a string, or the empty string
172     *   if that attribute does not have a specified or default value.
173     * @exception DOMException
174     *   NOT_SUPPORTED_ERR: May be raised if the implementation does not
175     *   support the feature <code>"XML"</code> and the language exposed
176     *   through the Document does not support XML Namespaces (such as [<a href='http://www.w3.org/TR/1999/REC-html401-19991224/'>HTML 4.01</a>]).
177     * @since DOM Level 2
178     */
179    public String getAttributeNS(String namespaceURI,
180                                 String localName)
181                                 throws DOMException;
182
183    /**
184     * Adds a new attribute. If an attribute with the same local name and
185     * namespace URI is already present on the element, its prefix is
186     * changed to be the prefix part of the <code>qualifiedName</code>, and
187     * its value is changed to be the <code>value</code> parameter. This
188     * value is a simple string; it is not parsed as it is being set. So any
189     * markup (such as syntax to be recognized as an entity reference) is
190     * treated as literal text, and needs to be appropriately escaped by the
191     * implementation when it is written out. In order to assign an
192     * attribute value that contains entity references, the user must create
193     * an <code>Attr</code> node plus any <code>Text</code> and
194     * <code>EntityReference</code> nodes, build the appropriate subtree,
195     * and use <code>setAttributeNodeNS</code> or
196     * <code>setAttributeNode</code> to assign it as the value of an
197     * attribute.
198     * <br>Per [<a href='http://www.w3.org/TR/1999/REC-xml-names-19990114/'>XML Namespaces</a>]
199     * , applications must use the value <code>null</code> as the
200     * <code>namespaceURI</code> parameter for methods if they wish to have
201     * no namespace.
202     * @param namespaceURI The namespace URI of the attribute to create or
203     *   alter.
204     * @param qualifiedName The qualified name of the attribute to create or
205     *   alter.
206     * @param value The value to set in string form.
207     * @exception DOMException
208     *   INVALID_CHARACTER_ERR: Raised if the specified qualified name is not
209     *   an XML name according to the XML version in use specified in the
210     *   <code>Document.xmlVersion</code> attribute.
211     *   <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
212     *   <br>NAMESPACE_ERR: Raised if the <code>qualifiedName</code> is
213     *   malformed per the Namespaces in XML specification, if the
214     *   <code>qualifiedName</code> has a prefix and the
215     *   <code>namespaceURI</code> is <code>null</code>, if the
216     *   <code>qualifiedName</code> has a prefix that is "xml" and the
217     *   <code>namespaceURI</code> is different from "<a href='http://www.w3.org/XML/1998/namespace'>
218     *   http://www.w3.org/XML/1998/namespace</a>", if the <code>qualifiedName</code> or its prefix is "xmlns" and the
219     *   <code>namespaceURI</code> is different from "<a href='http://www.w3.org/2000/xmlns/'>http://www.w3.org/2000/xmlns/</a>", or if the <code>namespaceURI</code> is "<a href='http://www.w3.org/2000/xmlns/'>http://www.w3.org/2000/xmlns/</a>" and neither the <code>qualifiedName</code> nor its prefix is "xmlns".
220     *   <br>NOT_SUPPORTED_ERR: May be raised if the implementation does not
221     *   support the feature <code>"XML"</code> and the language exposed
222     *   through the Document does not support XML Namespaces (such as [<a href='http://www.w3.org/TR/1999/REC-html401-19991224/'>HTML 4.01</a>]).
223     * @since DOM Level 2
224     */
225    public void setAttributeNS(String namespaceURI,
226                               String qualifiedName,
227                               String value)
228                               throws DOMException;
229
230    /**
231     * Removes an attribute by local name and namespace URI. If a default
232     * value for the removed attribute is defined in the DTD, a new
233     * attribute immediately appears with the default value as well as the
234     * corresponding namespace URI, local name, and prefix when applicable.
235     * The implementation may handle default values from other schemas
236     * similarly but applications should use
237     * <code>Document.normalizeDocument()</code> to guarantee this
238     * information is up-to-date.
239     * <br>If no attribute with this local name and namespace URI is found,
240     * this method has no effect.
241     * <br>Per [<a href='http://www.w3.org/TR/1999/REC-xml-names-19990114/'>XML Namespaces</a>]
242     * , applications must use the value <code>null</code> as the
243     * <code>namespaceURI</code> parameter for methods if they wish to have
244     * no namespace.
245     * @param namespaceURI The namespace URI of the attribute to remove.
246     * @param localName The local name of the attribute to remove.
247     * @exception DOMException
248     *   NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
249     *   <br>NOT_SUPPORTED_ERR: May be raised if the implementation does not
250     *   support the feature <code>"XML"</code> and the language exposed
251     *   through the Document does not support XML Namespaces (such as [<a href='http://www.w3.org/TR/1999/REC-html401-19991224/'>HTML 4.01</a>]).
252     * @since DOM Level 2
253     */
254    public void removeAttributeNS(String namespaceURI,
255                                  String localName)
256                                  throws DOMException;
257
258    /**
259     * Retrieves an <code>Attr</code> node by local name and namespace URI.
260     * <br>Per [<a href='http://www.w3.org/TR/1999/REC-xml-names-19990114/'>XML Namespaces</a>]
261     * , applications must use the value <code>null</code> as the
262     * <code>namespaceURI</code> parameter for methods if they wish to have
263     * no namespace.
264     * @param namespaceURI The namespace URI of the attribute to retrieve.
265     * @param localName The local name of the attribute to retrieve.
266     * @return The <code>Attr</code> node with the specified attribute local
267     *   name and namespace URI or <code>null</code> if there is no such
268     *   attribute.
269     * @exception DOMException
270     *   NOT_SUPPORTED_ERR: May be raised if the implementation does not
271     *   support the feature <code>"XML"</code> and the language exposed
272     *   through the Document does not support XML Namespaces (such as [<a href='http://www.w3.org/TR/1999/REC-html401-19991224/'>HTML 4.01</a>]).
273     * @since DOM Level 2
274     */
275    public Attr getAttributeNodeNS(String namespaceURI,
276                                   String localName)
277                                   throws DOMException;
278
279    /**
280     * Adds a new attribute. If an attribute with that local name and that
281     * namespace URI is already present in the element, it is replaced by
282     * the new one. Replacing an attribute node by itself has no effect.
283     * <br>Per [<a href='http://www.w3.org/TR/1999/REC-xml-names-19990114/'>XML Namespaces</a>]
284     * , applications must use the value <code>null</code> as the
285     * <code>namespaceURI</code> parameter for methods if they wish to have
286     * no namespace.
287     * @param newAttr The <code>Attr</code> node to add to the attribute list.
288     * @return If the <code>newAttr</code> attribute replaces an existing
289     *   attribute with the same local name and namespace URI, the replaced
290     *   <code>Attr</code> node is returned, otherwise <code>null</code> is
291     *   returned.
292     * @exception DOMException
293     *   WRONG_DOCUMENT_ERR: Raised if <code>newAttr</code> was created from a
294     *   different document than the one that created the element.
295     *   <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
296     *   <br>INUSE_ATTRIBUTE_ERR: Raised if <code>newAttr</code> is already an
297     *   attribute of another <code>Element</code> object. The DOM user must
298     *   explicitly clone <code>Attr</code> nodes to re-use them in other
299     *   elements.
300     *   <br>NOT_SUPPORTED_ERR: May be raised if the implementation does not
301     *   support the feature <code>"XML"</code> and the language exposed
302     *   through the Document does not support XML Namespaces (such as [<a href='http://www.w3.org/TR/1999/REC-html401-19991224/'>HTML 4.01</a>]).
303     * @since DOM Level 2
304     */
305    public Attr setAttributeNodeNS(Attr newAttr)
306                                   throws DOMException;
307
308    /**
309     * Returns a <code>NodeList</code> of all the descendant
310     * <code>Elements</code> with a given local name and namespace URI in
311     * document order.
312     * @param namespaceURI The namespace URI of the elements to match on. The
313     *   special value "*" matches all namespaces.
314     * @param localName The local name of the elements to match on. The
315     *   special value "*" matches all local names.
316     * @return A new <code>NodeList</code> object containing all the matched
317     *   <code>Elements</code>.
318     * @exception DOMException
319     *   NOT_SUPPORTED_ERR: May be raised if the implementation does not
320     *   support the feature <code>"XML"</code> and the language exposed
321     *   through the Document does not support XML Namespaces (such as [<a href='http://www.w3.org/TR/1999/REC-html401-19991224/'>HTML 4.01</a>]).
322     * @since DOM Level 2
323     */
324    public NodeList getElementsByTagNameNS(String namespaceURI,
325                                           String localName)
326                                           throws DOMException;
327
328    /**
329     * Returns <code>true</code> when an attribute with a given name is
330     * specified on this element or has a default value, <code>false</code>
331     * otherwise.
332     * @param name The name of the attribute to look for.
333     * @return <code>true</code> if an attribute with the given name is
334     *   specified on this element or has a default value, <code>false</code>
335     *    otherwise.
336     * @since DOM Level 2
337     */
338    public boolean hasAttribute(String name);
339
340    /**
341     * Returns <code>true</code> when an attribute with a given local name and
342     * namespace URI is specified on this element or has a default value,
343     * <code>false</code> otherwise.
344     * <br>Per [<a href='http://www.w3.org/TR/1999/REC-xml-names-19990114/'>XML Namespaces</a>]
345     * , applications must use the value <code>null</code> as the
346     * <code>namespaceURI</code> parameter for methods if they wish to have
347     * no namespace.
348     * @param namespaceURI The namespace URI of the attribute to look for.
349     * @param localName The local name of the attribute to look for.
350     * @return <code>true</code> if an attribute with the given local name
351     *   and namespace URI is specified or has a default value on this
352     *   element, <code>false</code> otherwise.
353     * @exception DOMException
354     *   NOT_SUPPORTED_ERR: May be raised if the implementation does not
355     *   support the feature <code>"XML"</code> and the language exposed
356     *   through the Document does not support XML Namespaces (such as [<a href='http://www.w3.org/TR/1999/REC-html401-19991224/'>HTML 4.01</a>]).
357     * @since DOM Level 2
358     */
359    public boolean hasAttributeNS(String namespaceURI,
360                                  String localName)
361                                  throws DOMException;
362
363    /**
364     *  The type information associated with this element.
365     * @since DOM Level 3
366     */
367    public TypeInfo getSchemaTypeInfo();
368
369    /**
370     *  If the parameter <code>isId</code> is <code>true</code>, this method
371     * declares the specified attribute to be a user-determined ID attribute
372     * . This affects the value of <code>Attr.isId</code> and the behavior
373     * of <code>Document.getElementById</code>, but does not change any
374     * schema that may be in use, in particular this does not affect the
375     * <code>Attr.schemaTypeInfo</code> of the specified <code>Attr</code>
376     * node. Use the value <code>false</code> for the parameter
377     * <code>isId</code> to undeclare an attribute for being a
378     * user-determined ID attribute.
379     * <br> To specify an attribute by local name and namespace URI, use the
380     * <code>setIdAttributeNS</code> method.
381     * @param name The name of the attribute.
382     * @param isId Whether the attribute is a of type ID.
383     * @exception DOMException
384     *   NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
385     *   <br>NOT_FOUND_ERR: Raised if the specified node is not an attribute
386     *   of this element.
387     * @since DOM Level 3
388     */
389    public void setIdAttribute(String name,
390                               boolean isId)
391                               throws DOMException;
392
393    /**
394     *  If the parameter <code>isId</code> is <code>true</code>, this method
395     * declares the specified attribute to be a user-determined ID attribute
396     * . This affects the value of <code>Attr.isId</code> and the behavior
397     * of <code>Document.getElementById</code>, but does not change any
398     * schema that may be in use, in particular this does not affect the
399     * <code>Attr.schemaTypeInfo</code> of the specified <code>Attr</code>
400     * node. Use the value <code>false</code> for the parameter
401     * <code>isId</code> to undeclare an attribute for being a
402     * user-determined ID attribute.
403     * @param namespaceURI The namespace URI of the attribute.
404     * @param localName The local name of the attribute.
405     * @param isId Whether the attribute is a of type ID.
406     * @exception DOMException
407     *   NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
408     *   <br>NOT_FOUND_ERR: Raised if the specified node is not an attribute
409     *   of this element.
410     * @since DOM Level 3
411     */
412    public void setIdAttributeNS(String namespaceURI,
413                                 String localName,
414                                 boolean isId)
415                                 throws DOMException;
416
417    /**
418     *  If the parameter <code>isId</code> is <code>true</code>, this method
419     * declares the specified attribute to be a user-determined ID attribute
420     * . This affects the value of <code>Attr.isId</code> and the behavior
421     * of <code>Document.getElementById</code>, but does not change any
422     * schema that may be in use, in particular this does not affect the
423     * <code>Attr.schemaTypeInfo</code> of the specified <code>Attr</code>
424     * node. Use the value <code>false</code> for the parameter
425     * <code>isId</code> to undeclare an attribute for being a
426     * user-determined ID attribute.
427     * @param idAttr The attribute node.
428     * @param isId Whether the attribute is a of type ID.
429     * @exception DOMException
430     *   NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly.
431     *   <br>NOT_FOUND_ERR: Raised if the specified node is not an attribute
432     *   of this element.
433     * @since DOM Level 3
434     */
435    public void setIdAttributeNode(Attr idAttr,
436                                   boolean isId)
437                                   throws DOMException;
438
439}
440