http://xml.apache.org/commons/components/external/: xml-commons provides an Apache-hosted set of DOM, SAX, and JAXP interfaces for use in other xml-based projects. Our hope is that we can standardize on both a common version and packaging scheme for these critical XML standards interfaces to make the lives of both our developers and users easier. The External Components portion of xml-commons contains interfaces that are defined by external standards organizations. For DOM, that's the W3C; for SAX it's David Megginson and sax.sourceforge.net; for JAXP it's Sun. 
/*
 * 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.stylesheets;


 The DocumentStyle interface provides a mechanism by which the 
style sheets embedded in a document can be retrieved. The expectation is 
that an instance of the DocumentStyle interface can be 
obtained by using binding-specific casting methods on an instance of the 
Document interface. 

See also the Document Object Model (DOM) Level 2 Style Specification.

Since:DOM Level 2
/**
 *  The <code>DocumentStyle</code> interface provides a mechanism by which the 
 * style sheets embedded in a document can be retrieved. The expectation is 
 * that an instance of the <code>DocumentStyle</code> interface can be 
 * obtained by using binding-specific casting methods on an instance of the 
 * <code>Document</code> interface. 
 * <p>See also the <a href='http://www.w3.org/TR/2000/REC-DOM-Level-2-Style-20001113'>Document Object Model (DOM) Level 2 Style Specification</a>.
 * @since DOM Level 2
 */
public interface DocumentStyle {
    
 A list containing all the style sheets explicitly linked into or 
embedded in a document. For HTML documents, this includes external 
style sheets, included via the HTML  LINK element, and inline  STYLE 
elements. In XML, this includes external style sheets, included via 
style sheet processing instructions (see [XML StyleSheet]). 

/**
     *  A list containing all the style sheets explicitly linked into or 
     * embedded in a document. For HTML documents, this includes external 
     * style sheets, included via the HTML  LINK element, and inline  STYLE 
     * elements. In XML, this includes external style sheets, included via 
     * style sheet processing instructions (see [XML StyleSheet]). 
     */
    public StyleSheetList getStyleSheets();

}