// -*- mode:C++; tab-width:2; c-basic-offset:2; indent-tabs-mode:nil -*-
//
// Copyright (C) 2000-2005 by Roger Rene Kommer / artefaktur, Kassel, Germany.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public License (LGPL).
//
//
// This library is distributed 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. See the
// License ACDK-FreeLicense document enclosed in the distribution
// for more for more details.
// This file is part of the Artefaktur Component Development Kit:
// ACDK
//
// Please refer to
// - http://www.acdk.de
// - http://www.artefaktur.com
// - http://acdk.sourceforge.net
// for more information.
//
// $Header: /cvsroot/acdk/acdk/acdk_xml/src/org/w3c/dom/Attr.h,v 1.10 2005/02/05 10:45:37 kommer Exp $
/*
Documentation:
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
*/
#ifndef org_w3c_dom_Attr_h
#define org_w3c_dom_Attr_h
#include "Node.h"
namespace org {
namespace w3c {
namespace dom {
ACDK_DECL_INTERFACE(Attr);
/**
* The <code>Attr</code> interface represents an attribute in an
* <code>Element</code> object. Typically the allowable values for the
* attribute are defined in a schema associated with the document.
* <p><code>Attr</code> objects inherit the <code>Node</code> interface, but
* since they are not actually child nodes of the element they describe, the
* DOM does not consider them part of the document tree. Thus, the
* <code>Node</code> attributes <code>parentNode</code>,
* <code>previousSibling</code>, and <code>nextSibling</code> have a
* <code>null</code> value for <code>Attr</code> objects. The DOM takes the
* view that attributes are properties of elements rather than having a
* separate identity from the elements they are associated with; this should
* make it more efficient to implement such features as default attributes
* associated with all elements of a given type. Furthermore,
* <code>Attr</code> nodes may not be immediate children of a
* <code>DocumentFragment</code>. However, they can be associated with
* <code>Element</code> nodes contained within a
* <code>DocumentFragment</code>. In short, users and implementors of the
* DOM need to be aware that <code>Attr</code> nodes have some things in
* common with other objects inheriting the <code>Node</code> interface, but
* they also are quite distinct.
* <p>The attribute's effective value is determined as follows: if this
* attribute has been explicitly assigned any value, that value is the
* attribute's effective value; otherwise, if there is a declaration for
* this attribute, and that declaration includes a default value, then that
* default value is the attribute's effective value; otherwise, the
* attribute does not exist on this element in the structure model until it
* has been explicitly added. Note that the <code>Node.nodeValue</code>
* attribute on the <code>Attr</code> instance can also be used to retrieve
* the string version of the attribute's value(s).
* <p> If the attribute was not explicitly given a value in the instance
* document but has a default value provided by the schema associated with
* the document, an attribute node will be created with
* <code>specified</code> set to <code>false</code>. Removing attribute
* nodes for which a default value is defined in the schema generates a new
* attribute node with the default value and <code>specified</code> set to
* <code>false</code>. If validation occurred while invoking
* <code>Document.normalizeDocument()</code>, attribute nodes with
* <code>specified</code> equals to <code>false</code> are recomputed
* according to the default attribute values provided by the schema. If no
* default value is associate with this attribute in the schema, the
* attribute node is discarded.
* <p>In XML, where the value of an attribute can contain entity references,
* the child nodes of the <code>Attr</code> node may be either
* <code>Text</code> or <code>EntityReference</code> nodes (when these are
* in use; see the description of <code>EntityReference</code> for
* discussion).
* <p>The DOM Core represents all attribute values as simple strings, even if
* the DTD or schema associated with the document declares them of some
* specific type such as tokenized.
* <p>The way attribute value normalization is performed by the DOM
* implementation depends on how much the implementation knows about the
* schema in use. Typically, the <code>value</code> and
* <code>nodeValue</code> attributes of an <code>Attr</code> node initially
* returns the normalized value given by the parser. It is also the case
* after <code>Document.normalizeDocument()</code> is called (assuming the
* right options have been set). But this may not be the case after
* mutation, independently of whether the mutation is performed by setting
* the string value directly or by changing the <code>Attr</code> child
* nodes. In particular, this is true when <a href='http://www.w3.org/TR/2004/REC-xml-20040204#dt-charref'>character
* references</a> are involved, given that they are not represented in the DOM and they
* impact attribute value normalization. On the other hand, if the
* implementation knows about the schema in use when the attribute value is
* changed, and it is of a different type than CDATA, it may normalize it
* again at that time. This is especially true of specialized DOM
* implementations, such as SVG DOM implementations, which store attribute
* values in an internal form different from a string.
* <p>The following table gives some examples of the relations between the
* attribute value in the original document (parsed attribute), the value as
* exposed in the DOM, and the serialization of the value:
* <table border='1' cellpadding='3'>
* <tr>
* <th>Examples</th>
* <th>Parsed
* attribute value</th>
* <th>Initial <code>Attr.value</code></th>
* <th>Serialized attribute value</th>
* </tr>
* <tr>
* <td valign='top' rowspan='1' colspan='1'>
* Character reference</td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"x&#178;=5"</pre>
* </td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"x\u00b2=5"</pre>
* </td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"x&#178;=5"</pre>
* </td>
* </tr>
* <tr>
* <td valign='top' rowspan='1' colspan='1'>Built-in
* character entity</td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"y&lt;6"</pre>
* </td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"y<6"</pre>
* </td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"y&lt;6"</pre>
* </td>
* </tr>
* <tr>
* <td valign='top' rowspan='1' colspan='1'>Literal newline between</td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>
* "x=5&#10;y=6"</pre>
* </td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"x=5 y=6"</pre>
* </td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"x=5&#10;y=6"</pre>
* </td>
* </tr>
* <tr>
* <td valign='top' rowspan='1' colspan='1'>Normalized newline between</td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"x=5
* y=6"</pre>
* </td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"x=5 y=6"</pre>
* </td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>"x=5 y=6"</pre>
* </td>
* </tr>
* <tr>
* <td valign='top' rowspan='1' colspan='1'>Entity <code>e</code> with literal newline</td>
* <td valign='top' rowspan='1' colspan='1'>
* <pre>
* <!ENTITY e '...&#10;...'> [...]> "x=5&e;y=6"</pre>
* </td>
* <td valign='top' rowspan='1' colspan='1'><em>Dependent on Implementation and Load Options</em></td>
* <td valign='top' rowspan='1' colspan='1'><em>Dependent on Implementation and Load/Save Options</em></td>
* </tr>
* </table>
* <p>See also the <a href='http://www.w3.org/TR/2004/REC-DOM-Level-3-Core-20040407'>Document acdk::lang::Object Model (DOM) Level 3 Core Specification</a>.
@author Roger Rene Kommer
@version $Revision: 1.10 $
@date $Date: 2005/02/05 10:45:37 $
*/
ACDK_INTERFACE class ACDK_ORG_XML_PUBLIC Attr
: implements Node
{
ACDK_WITH_METAINFO(Attr)
public:
/**
* Returns the name of this attribute. If <code>Node.localName</code> is
* different from <code>null</code>, this attribute is a qualified name.
*/
virtual RString getName() = 0;
/**
* <code>True</code> if this attribute was explicitly given a value in
* the instance document, <code>false</code> otherwise. If the
* application changed the value of this attribute node (even if it ends
* up having the same value as the default value) then it is set to
* <code>true</code>. The implementation may handle attributes with
* default values from other schemas similarly but applications should
* use <code>Document.normalizeDocument()</code> to guarantee this
* information is up-to-date.
*/
virtual bool getSpecified() = 0;
/**
* On retrieval, the value of the attribute is returned as a string.
* Character and general entity references are replaced with their
* values. See also the method <code>getAttribute</code> on the
* <code>Element</code> interface.
* <br>On setting, this creates a <code>Text</code> node with the unparsed
* contents of the string, i.e. any characters that an XML processor
* would recognize as markup are instead treated as literal text. See
* also the method <code>Element.setAttribute()</code>.
* <br> Some specialized implementations, such as some [<a href='http://www.w3.org/TR/2003/REC-SVG11-20030114/'>SVG 1.1</a>]
* implementations, may do normalization automatically, even after
* mutation; in such case, the value on retrieval may differ from the
* value on setting.
*/
virtual RString getValue() = 0;
/**
* On retrieval, the value of the attribute is returned as a string.
* Character and general entity references are replaced with their
* values. See also the method <code>getAttribute</code> on the
* <code>Element</code> interface.
* <br>On setting, this creates a <code>Text</code> node with the unparsed
* contents of the string, i.e. any characters that an XML processor
* would recognize as markup are instead treated as literal text. See
* also the method <code>Element.setAttribute()</code>.
* <br> Some specialized implementations, such as some [<a href='http://www.w3.org/TR/2003/REC-SVG11-20030114/'>SVG 1.1</a>]
* implementations, may do normalization automatically, even after
* mutation; in such case, the value on retrieval may differ from the
* value on setting.
* @exception DOMException
* NO_MODIFICATION_ALLOWED_ERR: Raised when the node is readonly.
*/
virtual void setValue(IN(RString) s) = 0;
/**
* The <code>Element</code> node this attribute is attached to or
* <code>null</code> if this attribute is not in use.
* @since DOM Level 2
@todo #### has to be implemented
*/
//virtual RElement getOwnerElement() = 0;
/**
* The type information associated with this attribute. While the type
* information contained in this attribute is guarantee to be correct
* after loading the document or invoking
* <code>Document.normalizeDocument()</code>, <code>schemaTypeInfo</code>
* may not be reliable if the node was moved.
* @since DOM Level 3
*/
//virtual RTypeInfo getSchemaTypeInfo() = 0;
/**
* Returns whether this attribute is known to be of type ID (i.e. to
* contain an identifier for its owner element) or not. When it is and
* its value is unique, the <code>ownerElement</code> of this attribute
* can be retrieved using the method <code>Document.getElementById</code>
* . The implementation could use several ways to determine if an
* attribute node is known to contain an identifier:
* <ul>
* <li> If validation
* occurred using an XML Schema [<a href='http://www.w3.org/TR/2001/REC-xmlschema-1-20010502/'>XML Schema Part 1</a>]
* while loading the document or while invoking
* <code>Document.normalizeDocument()</code>, the post-schema-validation
* infoset contributions (PSVI contributions) values are used to
* determine if this attribute is a schema-determined ID attribute using
* the <a href='http://www.w3.org/TR/2003/REC-xptr-framework-20030325/#term-sdi'>
* schema-determined ID</a> definition in [<a href='http://www.w3.org/TR/2003/REC-xptr-framework-20030325/'>XPointer</a>]
* .
* </li>
* <li> If validation occurred using a DTD while loading the document or
* 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
* attribute using the <a href='http://www.w3.org/TR/2003/REC-xptr-framework-20030325/#term-ddi'>
* DTD-determined ID</a> definition in [<a href='http://www.w3.org/TR/2003/REC-xptr-framework-20030325/'>XPointer</a>]
* .
* </li>
* <li> from the use of the methods <code>Element.setIdAttribute()</code>,
* <code>Element.setIdAttributeNS()</code>, or
* <code>Element.setIdAttributeNode()</code>, i.e. it is an
* user-determined ID attribute;
* <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>]
* ) consider the DOM user-determined ID attribute as being part of the
* XPointer externally-determined ID definition.
* </li>
* <li> using mechanisms that
* are outside the scope of this specification, it is then an
* externally-determined ID attribute. This includes using schema
* languages different from XML schema and DTD.
* </li>
* </ul>
* <br> If validation occurred while invoking
* <code>Document.normalizeDocument()</code>, all user-determined ID
* attributes are reset and all attribute nodes ID information are then
* reevaluated in accordance to the schema used. As a consequence, if
* the <code>Attr.schemaTypeInfo</code> attribute contains an ID type,
* <code>isId</code> will always return true.
* @since DOM Level 3
@todo #### has to be implemented
*/
// ### todo implement virtual bool isId() { return false; }
};
} // namespace dom
} // namespace w3c
} // namespace org
#endif //org_w3c_dom_Attr_h |
2005/5/9
Attr.h
