documentfragment.java

cssparser -- CSS 的语法解析器。采用java语言编写。可用在服务端生成页面。

/*
 * Copyright (c) 2000 World Wide Web Consortium,
 * (Massachusetts Institute of Technology, Institut National de
 * Recherche en Informatique et en Automatique, Keio University). All
 * Rights Reserved. This program is distributed under the W3C's Software
 * Intellectual Property License. This program 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 W3C License http://www.w3.org/Consortium/Legal/ for more details.
 */

package org.w3c.dom;

/**
 * <code>DocumentFragment</code> is a "lightweight" or "minimal" 
 * <code>Document</code> object. It is very common to want to be able to 
 * extract a portion of a document's tree or to create a new fragment of a 
 * document. Imagine implementing a user command like cut or rearranging a 
 * document by moving fragments around. It is desirable to have an object 
 * which can hold such fragments and it is quite natural to use a Node for 
 * this purpose. While it is true that a <code>Document</code> object could 
 * fulfill this role, a <code>Document</code> object can potentially be a 
 * heavyweight object, depending on the underlying implementation. What is 
 * really needed for this is a very lightweight object. 
 * <code>DocumentFragment</code> is such an object.
 * <p>Furthermore, various operations -- such as inserting nodes as children 
 * of another <code>Node</code> -- may take <code>DocumentFragment</code> 
 * objects as arguments; this results in all the child nodes of the 
 * <code>DocumentFragment</code> being moved to the child list of this node.
 * <p>The children of a <code>DocumentFragment</code> node are zero or more 
 * nodes representing the tops of any sub-trees defining the structure of 
 * the document. <code>DocumentFragment</code> nodes do not need to be 
 * well-formed XML documents (although they do need to follow the rules 
 * imposed upon well-formed XML parsed entities, which can have multiple top 
 * nodes). For example, a <code>DocumentFragment</code> might have only one 
 * child and that child node could be a <code>Text</code> node. Such a 
 * structure model represents neither an HTML document nor a well-formed XML 
 * document.
 * <p>When a <code>DocumentFragment</code> is inserted into a 
 * <code>Document</code> (or indeed any other <code>Node</code> that may 
 * take children) the children of the <code>DocumentFragment</code> and not 
 * the <code>DocumentFragment</code> itself are inserted into the 
 * <code>Node</code>. This makes the <code>DocumentFragment</code> very 
 * useful when the user wishes to create nodes that are siblings; the 
 * <code>DocumentFragment</code> acts as the parent of these nodes so that 
 * the user can use the standard methods from the <code>Node</code> 
 * interface, such as <code>insertBefore</code> and <code>appendChild</code>.
 * <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>.
 */
public interface DocumentFragment extends Node {
}