1 /* 2 * $Header$ 3 * $Revision$ 4 * $Date$ 5 * 6 * ==================================================================== 7 * 8 * Copyright 2000-2002 bob mcwhirter & James Strachan. 9 * All rights reserved. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions are 13 * met: 14 * 15 * * Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 18 * * Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions and the following disclaimer in the 20 * documentation and/or other materials provided with the distribution. 21 * 22 * * Neither the name of the Jaxen Project nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS 27 * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A 29 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER 30 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 31 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 32 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 33 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 34 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 35 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 36 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 37 * 38 * ==================================================================== 39 * This software consists of voluntary contributions made by many 40 * individuals on behalf of the Jaxen Project and was originally 41 * created by bob mcwhirter <bob@werken.com> and 42 * James Strachan <jstrachan@apache.org>. For more information on the 43 * Jaxen Project, please see <http://www.jaxen.org/>. 44 * 45 * $Id$ 46 */ 47 48 49 package org.jaxen.function; 50 51 import java.util.List; 52 53 import org.jaxen.Context; 54 import org.jaxen.Function; 55 import org.jaxen.FunctionCallException; 56 import org.jaxen.Navigator; 57 58 /** 59 * <p><b>4.1</b> <code><i>string</i> local-name(<i>node-set?</i>)</code></p> 60 * 61 * 62 * <blockquote cite="http://www.w3.org/TR/xpath"> 63 * The <b>local-name</b> function returns the local part of the 64 * expanded-name of the node in the argument node-set that is first in document order. 65 * If the argument node-set is empty or the first node has no expanded-name, an 66 * empty string is returned. If the argument is omitted, it defaults to a node-set with the context node as its only member. 67 * 68 * </blockquote> 69 * 70 * @author bob mcwhirter (bob @ werken.com) 71 * @see <a href="https://www.w3.org/TR/xpath#function-local-name" target="_top">Section 4.1 of the XPath Specification</a> 72 */ 73 public class LocalNameFunction implements Function 74 { 75 76 /** 77 * Create a new <code>LocalNameFunction</code> object. 78 */ 79 public LocalNameFunction() {} 80 81 /** 82 * Returns the local-name of the specified node or the context node if 83 * no arguments are provided. 84 * 85 * @param context the context at the point in the 86 * expression where the function is called 87 * @param args a <code>List</code> containing zero or one items 88 * 89 * @return a <code>String</code> containing the local-name 90 * 91 * @throws FunctionCallException if <code>args</code> has more than one item 92 */ 93 public Object call(Context context, 94 List args) throws FunctionCallException 95 { 96 if ( args.size() == 0 ) 97 { 98 return evaluate( context.getNodeSet(), 99 context.getNavigator() ); 100 } 101 102 if ( args.size() == 1 ) 103 { 104 return evaluate( args, 105 context.getNavigator() ); 106 } 107 108 throw new FunctionCallException( "local-name() requires zero or one argument." ); 109 } 110 111 /** 112 * Returns the local-name of <code>list.get(0)</code> 113 * 114 * @param list a list of nodes 115 * @param nav the <code>Navigator</code> used to retrieve the local name 116 * 117 * @return the local-name of <code>list.get(0)</code> 118 * 119 * @throws FunctionCallException if <code>list.get(0)</code> is not a node 120 */ 121 public static String evaluate(List list, 122 Navigator nav) throws FunctionCallException 123 { 124 if ( ! list.isEmpty() ) 125 { 126 Object first = list.get(0); 127 128 if (first instanceof List) 129 { 130 return evaluate( (List) first, 131 nav ); 132 } 133 else if ( nav.isElement( first ) ) 134 { 135 return nav.getElementName( first ); 136 } 137 else if ( nav.isAttribute( first ) ) 138 { 139 return nav.getAttributeName( first ); 140 } 141 else if ( nav.isProcessingInstruction( first ) ) 142 { 143 return nav.getProcessingInstructionTarget( first ); 144 } 145 else if ( nav.isNamespace( first ) ) 146 { 147 return nav.getNamespacePrefix( first ); 148 } 149 else if ( nav.isDocument( first ) ) 150 { 151 return ""; 152 } 153 else if ( nav.isComment( first ) ) 154 { 155 return ""; 156 } 157 else if ( nav.isText( first ) ) 158 { 159 return ""; 160 } 161 else { 162 throw new FunctionCallException("The argument to the local-name function must be a node-set"); 163 } 164 } 165 166 return ""; 167 } 168 169 } 170