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 // $Id: JAXPPrefixResolver.java 468655 2006-10-28 07:12:06Z minchau $ 19 20 package org.apache.xpath.jaxp; 21 22 import org.w3c.dom.Node; 23 import org.w3c.dom.NamedNodeMap; 24 import org.apache.xml.utils.PrefixResolver; 25 26 import javax.xml.namespace.NamespaceContext; 27 28 /** 29 * <meta name="usage" content="general"/> 30 * This class implements a Default PrefixResolver which 31 * can be used to perform prefix-to-namespace lookup 32 * for the XPath object. 33 * This class delegates the resolution to the passed NamespaceContext 34 */ 35 public class JAXPPrefixResolver implements PrefixResolver 36 { 37 38 private NamespaceContext namespaceContext; 39 40 JAXPPrefixResolver( NamespaceContext nsContext )41 public JAXPPrefixResolver ( NamespaceContext nsContext ) { 42 this.namespaceContext = nsContext; 43 } 44 45 getNamespaceForPrefix( String prefix )46 public String getNamespaceForPrefix( String prefix ) { 47 return namespaceContext.getNamespaceURI( prefix ); 48 } 49 50 /** 51 * Return the base identifier. 52 * 53 * @return null 54 */ getBaseIdentifier()55 public String getBaseIdentifier() { 56 return null; 57 } 58 59 /** 60 * @see PrefixResolver#handlesNullPrefixes() 61 */ handlesNullPrefixes()62 public boolean handlesNullPrefixes() { 63 return false; 64 } 65 66 67 /** 68 * The URI for the XML namespace. 69 * (Duplicate of that found in org.apache.xpath.XPathContext). 70 */ 71 72 public static final String S_XMLNAMESPACEURI = 73 "http://www.w3.org/XML/1998/namespace"; 74 75 76 /** 77 * Given a prefix and a Context Node, get the corresponding namespace. 78 * Warning: This will not work correctly if namespaceContext 79 * is an attribute node. 80 * @param prefix Prefix to resolve. 81 * @param namespaceContext Node from which to start searching for a 82 * xmlns attribute that binds a prefix to a namespace. 83 * @return Namespace that prefix resolves to, or null if prefix 84 * is not bound. 85 */ getNamespaceForPrefix(String prefix, org.w3c.dom.Node namespaceContext)86 public String getNamespaceForPrefix(String prefix, 87 org.w3c.dom.Node namespaceContext) { 88 Node parent = namespaceContext; 89 String namespace = null; 90 91 if (prefix.equals("xml")) { 92 namespace = S_XMLNAMESPACEURI; 93 } else { 94 int type; 95 96 while ((null != parent) && (null == namespace) 97 && (((type = parent.getNodeType()) == Node.ELEMENT_NODE) 98 || (type == Node.ENTITY_REFERENCE_NODE))) { 99 100 if (type == Node.ELEMENT_NODE) { 101 NamedNodeMap nnm = parent.getAttributes(); 102 103 for (int i = 0; i < nnm.getLength(); i++) { 104 Node attr = nnm.item(i); 105 String aname = attr.getNodeName(); 106 boolean isPrefix = aname.startsWith("xmlns:"); 107 108 if (isPrefix || aname.equals("xmlns")) { 109 int index = aname.indexOf(':'); 110 String p =isPrefix ?aname.substring(index + 1) :""; 111 112 if (p.equals(prefix)) { 113 namespace = attr.getNodeValue(); 114 break; 115 } 116 } 117 } 118 } 119 120 parent = parent.getParentNode(); 121 } 122 } 123 return namespace; 124 } 125 126 } 127 128