/*
 * 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.css;

/**
 * The <code>CSSRuleList</code> interface provides the abstraction of an
 * ordered collection of CSS rules.
 * <p>
 * The items in the <code>CSSRuleList</code> are accessible via an integral
 * index, starting from 0.
 * <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 CSSRuleList {
	/**
	 * The number of <code>CSSRules</code> in the list. The range of valid
	 * child rule indices is <code>0</code> to <code>length-1</code>
	 * inclusive.
	 */
	public int getLength();

	/**
	 * Used to retrieve a CSS rule by ordinal index. The order in this
	 * collection represents the order of the rules in the CSS style sheet. If
	 * index is greater than or equal to the number of rules in the list, this
	 * returns <code>null</code>.
	 * 
	 * @param indexIndex
	 *            into the collection
	 * @return The style rule at the <code>index</code> position in the
	 *         <code>CSSRuleList</code>, or <code>null</code> if that is
	 *         not a valid index.
	 */
	public CSSRule item(int index);

}