001/* 002 * Copyright (c) 2000 World Wide Web Consortium, 003 * (Massachusetts Institute of Technology, Institut National de 004 * Recherche en Informatique et en Automatique, Keio University). All 005 * Rights Reserved. This program is distributed under the W3C's Software 006 * Intellectual Property License. This program is distributed in the 007 * hope that it will be useful, but WITHOUT ANY WARRANTY; without even 008 * the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR 009 * PURPOSE. 010 * See W3C License http://www.w3.org/Consortium/Legal/ for more details. 011 */ 012 013package org.w3c.dom; 014 015/** 016 * The <code>Element</code> interface represents an element in an HTML or XML 017 * document. Elements may have attributes associated with them; since the 018 * <code>Element</code> interface inherits from <code>Node</code>, the 019 * generic <code>Node</code> interface attribute <code>attributes</code> may 020 * be used to retrieve the set of all attributes for an element. There are 021 * methods on the <code>Element</code> interface to retrieve either an 022 * <code>Attr</code> object by name or an attribute value by name. In XML, 023 * where an attribute value may contain entity references, an 024 * <code>Attr</code> object should be retrieved to examine the possibly 025 * fairly complex sub-tree representing the attribute value. On the other 026 * hand, in HTML, where all attributes have simple string values, methods to 027 * directly access an attribute value can safely be used as a convenience.In 028 * DOM Level 2, the method <code>normalize</code> is inherited from the 029 * <code>Node</code> interface where it was moved. 030 * <p>See also the <a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Core-20001113'>Document Object Model (DOM) Level 2 Core Specification</a>. 031 */ 032public interface Element extends Node { 033 /** 034 * The name of the element. For example, in: 035 * <pre> <elementExample 036 * id="demo"> ... </elementExample> , </pre> 037 * <code>tagName</code> has 038 * the value <code>"elementExample"</code>. Note that this is 039 * case-preserving in XML, as are all of the operations of the DOM. The 040 * HTML DOM returns the <code>tagName</code> of an HTML element in the 041 * canonical uppercase form, regardless of the case in the source HTML 042 * document. 043 */ 044 public String getTagName(); 045 046 /** 047 * Retrieves an attribute value by name. 048 * @param nameThe name of the attribute to retrieve. 049 * @return The <code>Attr</code> value as a string, or the empty string 050 * if that attribute does not have a specified or default value. 051 */ 052 public String getAttribute(String name); 053 054 /** 055 * Adds a new attribute. If an attribute with that name is already present 056 * in the element, its value is changed to be that of the value 057 * parameter. This value is a simple string; it is not parsed as it is 058 * being set. So any markup (such as syntax to be recognized as an 059 * entity reference) is treated as literal text, and needs to be 060 * appropriately escaped by the implementation when it is written out. 061 * In order to assign an attribute value that contains entity 062 * references, the user must create an <code>Attr</code> node plus any 063 * <code>Text</code> and <code>EntityReference</code> nodes, build the 064 * appropriate subtree, and use <code>setAttributeNode</code> to assign 065 * it as the value of an attribute. 066 * <br>To set an attribute with a qualified name and namespace URI, use 067 * the <code>setAttributeNS</code> method. 068 * @param nameThe name of the attribute to create or alter. 069 * @param valueValue to set in string form. 070 * @exception DOMException 071 * INVALID_CHARACTER_ERR: Raised if the specified name contains an 072 * illegal character. 073 * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. 074 */ 075 public void setAttribute(String name, 076 String value) 077 throws DOMException; 078 079 /** 080 * Removes an attribute by name. If the removed attribute is known to have 081 * a default value, an attribute immediately appears containing the 082 * default value as well as the corresponding namespace URI, local name, 083 * and prefix when applicable. 084 * <br>To remove an attribute by local name and namespace URI, use the 085 * <code>removeAttributeNS</code> method. 086 * @param nameThe name of the attribute to remove. 087 * @exception DOMException 088 * NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. 089 */ 090 public void removeAttribute(String name) 091 throws DOMException; 092 093 /** 094 * Retrieves an attribute node by name. 095 * <br>To retrieve an attribute node by qualified name and namespace URI, 096 * use the <code>getAttributeNodeNS</code> method. 097 * @param nameThe name (<code>nodeName</code>) of the attribute to 098 * retrieve. 099 * @return The <code>Attr</code> node with the specified name ( 100 * <code>nodeName</code>) or <code>null</code> if there is no such 101 * attribute. 102 */ 103 public Attr getAttributeNode(String name); 104 105 /** 106 * Adds a new attribute node. If an attribute with that name ( 107 * <code>nodeName</code>) is already present in the element, it is 108 * replaced by the new one. 109 * <br>To add a new attribute node with a qualified name and namespace 110 * URI, use the <code>setAttributeNodeNS</code> method. 111 * @param newAttrThe <code>Attr</code> node to add to the attribute list. 112 * @return If the <code>newAttr</code> attribute replaces an existing 113 * attribute, the replaced <code>Attr</code> node is returned, 114 * otherwise <code>null</code> is returned. 115 * @exception DOMException 116 * WRONG_DOCUMENT_ERR: Raised if <code>newAttr</code> was created from a 117 * different document than the one that created the element. 118 * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. 119 * <br>INUSE_ATTRIBUTE_ERR: Raised if <code>newAttr</code> is already an 120 * attribute of another <code>Element</code> object. The DOM user must 121 * explicitly clone <code>Attr</code> nodes to re-use them in other 122 * elements. 123 */ 124 public Attr setAttributeNode(Attr newAttr) 125 throws DOMException; 126 127 /** 128 * Removes the specified attribute node. If the removed <code>Attr</code> 129 * has a default value it is immediately replaced. The replacing 130 * attribute has the same namespace URI and local name, as well as the 131 * original prefix, when applicable. 132 * @param oldAttrThe <code>Attr</code> node to remove from the attribute 133 * list. 134 * @return The <code>Attr</code> node that was removed. 135 * @exception DOMException 136 * NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. 137 * <br>NOT_FOUND_ERR: Raised if <code>oldAttr</code> is not an attribute 138 * of the element. 139 */ 140 public Attr removeAttributeNode(Attr oldAttr) 141 throws DOMException; 142 143 /** 144 * Returns a <code>NodeList</code> of all descendant <code>Elements</code> 145 * with a given tag name, in the order in which they are encountered in 146 * a preorder traversal of this <code>Element</code> tree. 147 * @param nameThe name of the tag to match on. The special value "*" 148 * matches all tags. 149 * @return A list of matching <code>Element</code> nodes. 150 */ 151 public NodeList getElementsByTagName(String name); 152 153 /** 154 * Retrieves an attribute value by local name and namespace URI. HTML-only 155 * DOM implementations do not need to implement this method. 156 * @param namespaceURIThe namespace URI of the attribute to retrieve. 157 * @param localNameThe local name of the attribute to retrieve. 158 * @return The <code>Attr</code> value as a string, or the empty string 159 * if that attribute does not have a specified or default value. 160 * @since DOM Level 2 161 */ 162 public String getAttributeNS(String namespaceURI, 163 String localName); 164 165 /** 166 * Adds a new attribute. If an attribute with the same local name and 167 * namespace URI is already present on the element, its prefix is 168 * changed to be the prefix part of the <code>qualifiedName</code>, and 169 * its value is changed to be the <code>value</code> parameter. This 170 * value is a simple string; it is not parsed as it is being set. So any 171 * markup (such as syntax to be recognized as an entity reference) is 172 * treated as literal text, and needs to be appropriately escaped by the 173 * implementation when it is written out. In order to assign an 174 * attribute value that contains entity references, the user must create 175 * an <code>Attr</code> node plus any <code>Text</code> and 176 * <code>EntityReference</code> nodes, build the appropriate subtree, 177 * and use <code>setAttributeNodeNS</code> or 178 * <code>setAttributeNode</code> to assign it as the value of an 179 * attribute. 180 * <br>HTML-only DOM implementations do not need to implement this method. 181 * @param namespaceURIThe namespace URI of the attribute to create or 182 * alter. 183 * @param qualifiedNameThe qualified name of the attribute to create or 184 * alter. 185 * @param valueThe value to set in string form. 186 * @exception DOMException 187 * INVALID_CHARACTER_ERR: Raised if the specified qualified name 188 * contains an illegal character. 189 * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. 190 * <br>NAMESPACE_ERR: Raised if the <code>qualifiedName</code> is 191 * malformed, if the <code>qualifiedName</code> has a prefix and the 192 * <code>namespaceURI</code> is <code>null</code>, if the 193 * <code>qualifiedName</code> has a prefix that is "xml" and the 194 * <code>namespaceURI</code> is different from " 195 * http://www.w3.org/XML/1998/namespace", or if the 196 * <code>qualifiedName</code> is "xmlns" and the 197 * <code>namespaceURI</code> is different from " 198 * http://www.w3.org/2000/xmlns/". 199 * @since DOM Level 2 200 */ 201 public void setAttributeNS(String namespaceURI, 202 String qualifiedName, 203 String value) 204 throws DOMException; 205 206 /** 207 * Removes an attribute by local name and namespace URI. If the removed 208 * attribute has a default value it is immediately replaced. The 209 * replacing attribute has the same namespace URI and local name, as 210 * well as the original prefix. 211 * <br>HTML-only DOM implementations do not need to implement this method. 212 * @param namespaceURIThe namespace URI of the attribute to remove. 213 * @param localNameThe local name of the attribute to remove. 214 * @exception DOMException 215 * NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. 216 * @since DOM Level 2 217 */ 218 public void removeAttributeNS(String namespaceURI, 219 String localName) 220 throws DOMException; 221 222 /** 223 * Retrieves an <code>Attr</code> node by local name and namespace URI. 224 * HTML-only DOM implementations do not need to implement this method. 225 * @param namespaceURIThe namespace URI of the attribute to retrieve. 226 * @param localNameThe local name of the attribute to retrieve. 227 * @return The <code>Attr</code> node with the specified attribute local 228 * name and namespace URI or <code>null</code> if there is no such 229 * attribute. 230 * @since DOM Level 2 231 */ 232 public Attr getAttributeNodeNS(String namespaceURI, 233 String localName); 234 235 /** 236 * Adds a new attribute. If an attribute with that local name and that 237 * namespace URI is already present in the element, it is replaced by 238 * the new one. 239 * <br>HTML-only DOM implementations do not need to implement this method. 240 * @param newAttrThe <code>Attr</code> node to add to the attribute list. 241 * @return If the <code>newAttr</code> attribute replaces an existing 242 * attribute with the same local name and namespace URI, the replaced 243 * <code>Attr</code> node is returned, otherwise <code>null</code> is 244 * returned. 245 * @exception DOMException 246 * WRONG_DOCUMENT_ERR: Raised if <code>newAttr</code> was created from a 247 * different document than the one that created the element. 248 * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. 249 * <br>INUSE_ATTRIBUTE_ERR: Raised if <code>newAttr</code> is already an 250 * attribute of another <code>Element</code> object. The DOM user must 251 * explicitly clone <code>Attr</code> nodes to re-use them in other 252 * elements. 253 * @since DOM Level 2 254 */ 255 public Attr setAttributeNodeNS(Attr newAttr) 256 throws DOMException; 257 258 /** 259 * Returns a <code>NodeList</code> of all the descendant 260 * <code>Elements</code> with a given local name and namespace URI in 261 * the order in which they are encountered in a preorder traversal of 262 * this <code>Element</code> tree. 263 * <br>HTML-only DOM implementations do not need to implement this method. 264 * @param namespaceURIThe namespace URI of the elements to match on. The 265 * special value "*" matches all namespaces. 266 * @param localNameThe local name of the elements to match on. The 267 * special value "*" matches all local names. 268 * @return A new <code>NodeList</code> object containing all the matched 269 * <code>Elements</code>. 270 * @since DOM Level 2 271 */ 272 public NodeList getElementsByTagNameNS(String namespaceURI, 273 String localName); 274 275 /** 276 * Returns <code>true</code> when an attribute with a given name is 277 * specified on this element or has a default value, <code>false</code> 278 * otherwise. 279 * @param nameThe name of the attribute to look for. 280 * @return <code>true</code> if an attribute with the given name is 281 * specified on this element or has a default value, <code>false</code> 282 * otherwise. 283 * @since DOM Level 2 284 */ 285 public boolean hasAttribute(String name); 286 287 /** 288 * Returns <code>true</code> when an attribute with a given local name and 289 * namespace URI is specified on this element or has a default value, 290 * <code>false</code> otherwise. HTML-only DOM implementations do not 291 * need to implement this method. 292 * @param namespaceURIThe namespace URI of the attribute to look for. 293 * @param localNameThe local name of the attribute to look for. 294 * @return <code>true</code> if an attribute with the given local name 295 * and namespace URI is specified or has a default value on this 296 * element, <code>false</code> otherwise. 297 * @since DOM Level 2 298 */ 299 public boolean hasAttributeNS(String namespaceURI, 300 String localName); 301 302}