📄 element.java
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/* * Copyright (c) 2004 World Wide Web Consortium, * * (Massachusetts Institute of Technology, European Research Consortium for * Informatics and Mathematics, Keio University). All Rights Reserved. This * work is distributed under the W3C(r) Software License [1] in the hope that * it will be useful, but WITHOUT ANY WARRANTY; without even the implied * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. * * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231 */package org.w3c.dom;/** * The <code>Element</code> interface represents an element in an HTML or XML * document. Elements may have attributes associated with them; since the * <code>Element</code> interface inherits from <code>Node</code>, the * generic <code>Node</code> interface attribute <code>attributes</code> may * be used to retrieve the set of all attributes for an element. There are * methods on the <code>Element</code> interface to retrieve either an * <code>Attr</code> object by name or an attribute value by name. In XML, * where an attribute value may contain entity references, an * <code>Attr</code> object should be retrieved to examine the possibly * fairly complex sub-tree representing the attribute value. On the other * hand, in HTML, where all attributes have simple string values, methods to * directly access an attribute value can safely be used as a convenience. * <p ><b>Note:</b> In DOM Level 2, the method <code>normalize</code> is * inherited from the <code>Node</code> interface where it was moved. * <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>. */public interface Element extends Node { /** * The name of the element. If <code>Node.localName</code> is different * from <code>null</code>, this attribute is a qualified name. For * example, in: * <pre> <elementExample id="demo"> ... * </elementExample> , </pre> * <code>tagName</code> has the value * <code>"elementExample"</code>. Note that this is case-preserving in * XML, as are all of the operations of the DOM. The HTML DOM returns * the <code>tagName</code> of an HTML element in the canonical * uppercase form, regardless of the case in the source HTML document. */ public String getTagName(); /** * Retrieves an attribute value by name. * @param name The name of the attribute to retrieve. * @return The <code>Attr</code> value as a string, or the empty string * if that attribute does not have a specified or default value. */ public String getAttribute(String name); /** * Adds a new attribute. If an attribute with that name is already present * in the element, its value is changed to be that of the value * parameter. This value is a simple string; it is not parsed as it is * being set. So any markup (such as syntax to be recognized as an * entity reference) is treated as literal text, and needs to be * appropriately escaped by the implementation when it is written out. * In order to assign an attribute value that contains entity * references, the user must create an <code>Attr</code> node plus any * <code>Text</code> and <code>EntityReference</code> nodes, build the * appropriate subtree, and use <code>setAttributeNode</code> to assign * it as the value of an attribute. * <br>To set an attribute with a qualified name and namespace URI, use * the <code>setAttributeNS</code> method. * @param name The name of the attribute to create or alter. * @param value Value to set in string form. * @exception DOMException * INVALID_CHARACTER_ERR: Raised if the specified name is not an XML * name according to the XML version in use specified in the * <code>Document.xmlVersion</code> attribute. * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. */ public void setAttribute(String name, String value) throws DOMException; /** * Removes an attribute by name. If a default value for the removed * attribute is defined in the DTD, a new attribute immediately appears * with the default value as well as the corresponding namespace URI, * local name, and prefix when applicable. The implementation may handle * default values from other schemas similarly but applications should * use <code>Document.normalizeDocument()</code> to guarantee this * information is up-to-date. * <br>If no attribute with this name is found, this method has no effect. * <br>To remove an attribute by local name and namespace URI, use the * <code>removeAttributeNS</code> method. * @param name The name of the attribute to remove. * @exception DOMException * NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. */ public void removeAttribute(String name) throws DOMException; /** * Retrieves an attribute node by name. * <br>To retrieve an attribute node by qualified name and namespace URI, * use the <code>getAttributeNodeNS</code> method. * @param name The name (<code>nodeName</code>) of the attribute to * retrieve. * @return The <code>Attr</code> node with the specified name ( * <code>nodeName</code>) or <code>null</code> if there is no such * attribute. */ public Attr getAttributeNode(String name); /** * Adds a new attribute node. If an attribute with that name ( * <code>nodeName</code>) is already present in the element, it is * replaced by the new one. Replacing an attribute node by itself has no * effect. * <br>To add a new attribute node with a qualified name and namespace * URI, use the <code>setAttributeNodeNS</code> method. * @param newAttr The <code>Attr</code> node to add to the attribute list. * @return If the <code>newAttr</code> attribute replaces an existing * attribute, the replaced <code>Attr</code> node is returned, * otherwise <code>null</code> is returned. * @exception DOMException * WRONG_DOCUMENT_ERR: Raised if <code>newAttr</code> was created from a * different document than the one that created the element. * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. * <br>INUSE_ATTRIBUTE_ERR: Raised if <code>newAttr</code> is already an * attribute of another <code>Element</code> object. The DOM user must * explicitly clone <code>Attr</code> nodes to re-use them in other * elements. */ public Attr setAttributeNode(Attr newAttr) throws DOMException; /** * Removes the specified attribute node. If a default value for the * removed <code>Attr</code> node is defined in the DTD, a new node * immediately appears with the default value as well as the * corresponding namespace URI, local name, and prefix when applicable. * The implementation may handle default values from other schemas * similarly but applications should use * <code>Document.normalizeDocument()</code> to guarantee this * information is up-to-date. * @param oldAttr The <code>Attr</code> node to remove from the attribute * list. * @return The <code>Attr</code> node that was removed. * @exception DOMException * NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. * <br>NOT_FOUND_ERR: Raised if <code>oldAttr</code> is not an attribute * of the element. */ public Attr removeAttributeNode(Attr oldAttr) throws DOMException; /** * Returns a <code>NodeList</code> of all descendant <code>Elements</code> * with a given tag name, in document order. * @param name The name of the tag to match on. The special value "*" * matches all tags. * @return A list of matching <code>Element</code> nodes. */ public NodeList getElementsByTagName(String name); /** * Retrieves an attribute value by local name and namespace URI. * <br>Per [<a href='http://www.w3.org/TR/1999/REC-xml-names-19990114/'>XML Namespaces</a>] * , applications must use the value <code>null</code> as the * <code>namespaceURI</code> parameter for methods if they wish to have * no namespace. * @param namespaceURI The namespace URI of the attribute to retrieve. * @param localName The local name of the attribute to retrieve. * @return The <code>Attr</code> value as a string, or the empty string * if that attribute does not have a specified or default value. * @exception DOMException * NOT_SUPPORTED_ERR: May be raised if the implementation does not * support the feature <code>"XML"</code> and the language exposed * 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>]). * @since DOM Level 2 */ public String getAttributeNS(String namespaceURI, String localName) throws DOMException; /** * Adds a new attribute. If an attribute with the same local name and * namespace URI is already present on the element, its prefix is * changed to be the prefix part of the <code>qualifiedName</code>, and * its value is changed to be the <code>value</code> parameter. This * value is a simple string; it is not parsed as it is being set. So any * markup (such as syntax to be recognized as an entity reference) is * treated as literal text, and needs to be appropriately escaped by the * implementation when it is written out. In order to assign an * attribute value that contains entity references, the user must create * an <code>Attr</code> node plus any <code>Text</code> and * <code>EntityReference</code> nodes, build the appropriate subtree, * and use <code>setAttributeNodeNS</code> or * <code>setAttributeNode</code> to assign it as the value of an * attribute. * <br>Per [<a href='http://www.w3.org/TR/1999/REC-xml-names-19990114/'>XML Namespaces</a>] * , applications must use the value <code>null</code> as the * <code>namespaceURI</code> parameter for methods if they wish to have * no namespace. * @param namespaceURI The namespace URI of the attribute to create or * alter. * @param qualifiedName The qualified name of the attribute to create or * alter. * @param value The value to set in string form. * @exception DOMException * INVALID_CHARACTER_ERR: Raised if the specified qualified name is not * an XML name according to the XML version in use specified in the * <code>Document.xmlVersion</code> attribute. * <br>NO_MODIFICATION_ALLOWED_ERR: Raised if this node is readonly. * <br>NAMESPACE_ERR: Raised if the <code>qualifiedName</code> is * malformed per the Namespaces in XML specification, if the * <code>qualifiedName</code> has a prefix and the * <code>namespaceURI</code> is <code>null</code>, if the * <code>qualifiedName</code> has a prefix that is "xml" and the * <code>namespaceURI</code> is different from "<a href='http://www.w3.org/XML/1998/namespace'> * http://www.w3.org/XML/1998/namespace</a>", if the <code>qualifiedName</code> or its prefix is "xmlns" and the * <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". * <br>NOT_SUPPORTED_ERR: May be raised if the implementation does not
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