001    /*
002     * Copyright (c) 2004 World Wide Web Consortium,
003     *
004     * (Massachusetts Institute of Technology, European Research Consortium for
005     * Informatics and Mathematics, Keio University). All Rights Reserved. This
006     * work is distributed under the W3C(r) Software License [1] in the hope that
007     * it will be useful, but WITHOUT ANY WARRANTY; without even the implied
008     * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
009     *
010     * [1] http://www.w3.org/Consortium/Legal/2002/copyright-software-20021231
011     */
012    
013    package org.w3c.dom.xpath;
014    
015    /**
016     * The <code>XPathNSResolver</code> interface permit <code>prefix</code>
017     * strings in the expression to be properly bound to
018     * <code>namespaceURI</code> strings. <code>XPathEvaluator</code> can
019     * construct an implementation of <code>XPathNSResolver</code> from a node,
020     * or the interface may be implemented by any application.
021     * <p>See also the <a href='http://www.w3.org/TR/2004/NOTE-DOM-Level-3-XPath-20040226'>Document Object Model (DOM) Level 3 XPath Specification</a>.
022     */
023    public interface XPathNSResolver {
024        /**
025         * Look up the namespace URI associated to the given namespace prefix. The
026         * XPath evaluator must never call this with a <code>null</code> or
027         * empty argument, because the result of doing this is undefined.
028         * @param prefix The prefix to look for.
029         * @return Returns the associated namespace URI or <code>null</code> if
030         *   none is found.
031         */
032        public String lookupNamespaceURI(String prefix);
033    
034    }