1/*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the  "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
9 *
10 *     http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18/*
19 * $Id: PrefixResolver.java 468655 2006-10-28 07:12:06Z minchau $
20 */
21package org.apache.xml.utils;
22
23/**
24 * The class that implements this interface can resolve prefixes to
25 * namespaces. Examples would include resolving the meaning of a
26 * prefix at a particular point in a document, or mapping the prefixes
27 * used in an XPath expression.
28 * @xsl.usage advanced
29 */
30public interface PrefixResolver
31{
32
33  /**
34   * Given a namespace, get the corrisponding prefix.  This assumes that
35   * the PrefixResolver holds its own namespace context, or is a namespace
36   * context itself.
37   *
38   * @param prefix The prefix to look up, which may be an empty string ("") for the default Namespace.
39   *
40   * @return The associated Namespace URI, or null if the prefix
41   *         is undeclared in this context.
42   */
43  String getNamespaceForPrefix(String prefix);
44
45  /**
46   * Given a namespace, get the corresponding prefix, based on the context node.
47   *
48   * @param prefix The prefix to look up, which may be an empty string ("") for the default Namespace.
49   * @param context The node context from which to look up the URI.
50   *
51   * @return The associated Namespace URI as a string, or null if the prefix
52   *         is undeclared in this context.
53   */
54  String getNamespaceForPrefix(String prefix, org.w3c.dom.Node context);
55
56  /**
57   * Return the base identifier.
58   *
59   * @return The base identifier from where relative URIs should be absolutized, or null
60   * if the base ID is unknown.
61   * <p>
62   * CAVEAT: Note that the base URI in an XML document may vary with where
63   * you are in the document, if part of the doc's contents were brought in
64   * via an external entity reference or if mechanisms such as xml:base have
65   * been used. Unless this PrefixResolver is bound to a specific portion of
66   * the document, or has been kept up to date via some other mechanism, it
67   * may not accurately reflect that context information.
68   */
69  public String getBaseIdentifier();
70
71  public boolean handlesNullPrefixes();
72}
73