1 /* 2 * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/function/IdFunction.java,v 1.6 2003/06/29 18:04:41 ssanders Exp $ 3 * $Revision: 1.6 $ 4 * $Date: 2003/06/29 18:04:41 $ 5 * 6 * ==================================================================== 7 * 8 * Copyright (C) 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 13 * are met: 14 * 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions, and the following disclaimer. 17 * 18 * 2. Redistributions in binary form must reproduce the above copyright 19 * notice, this list of conditions, and the disclaimer that follows 20 * these conditions in the documentation and/or other materials 21 * provided with the distribution. 22 * 23 * 3. The name "Jaxen" must not be used to endorse or promote products 24 * derived from this software without prior written permission. For 25 * written permission, please contact license@jaxen.org. 26 * 27 * 4. Products derived from this software may not be called "Jaxen", nor 28 * may "Jaxen" appear in their name, without prior written permission 29 * from the Jaxen Project Management (pm@jaxen.org). 30 * 31 * In addition, we request (but do not require) that you include in the 32 * end-user documentation provided with the redistribution and/or in the 33 * software itself an acknowledgement equivalent to the following: 34 * "This product includes software developed by the 35 * Jaxen Project (http://www.jaxen.org/)." 36 * Alternatively, the acknowledgment may be graphical using the logos 37 * available at http://www.jaxen.org/ 38 * 39 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED 40 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 41 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 42 * DISCLAIMED. IN NO EVENT SHALL THE Jaxen AUTHORS OR THE PROJECT 43 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 44 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 45 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF 46 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND 47 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 48 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 49 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 50 * SUCH DAMAGE. 51 * 52 * ==================================================================== 53 * This software consists of voluntary contributions made by many 54 * individuals on behalf of the Jaxen Project and was originally 55 * created by bob mcwhirter <bob@werken.com> and 56 * James Strachan <jstrachan@apache.org>. For more information on the 57 * Jaxen Project, please see <http://www.jaxen.org/>. 58 * 59 * $Id: IdFunction.java,v 1.6 2003/06/29 18:04:41 ssanders Exp $ 60 */ 61 62 package org.jaxen.function; 63 64 import java.util.ArrayList; 65 import java.util.Collections; 66 import java.util.Iterator; 67 import java.util.List; 68 import java.util.StringTokenizer; 69 70 import org.jaxen.Context; 71 import org.jaxen.Function; 72 import org.jaxen.FunctionCallException; 73 import org.jaxen.Navigator; 74 75 /*** 76 * <p><b>4.1</b> <code><i>node-set</i> id(<i>object</i>)</code> 77 * 78 * @author Erwin Bolwidt (ejb @ klomp.org) 79 * @author J\u00e9r\u00f4me N\u00e8gre (jerome.negre @ e-xmlmedia.fr) 80 */ 81 public class IdFunction implements Function 82 { 83 84 public Object call (Context context, List args) throws FunctionCallException 85 { 86 if ( args.size() == 1 ) { 87 return evaluate( context.getNodeSet(), 88 args.get(0), context.getNavigator() ); 89 } 90 91 throw new FunctionCallException( "id() requires one argument" ); 92 } 93 94 public static List evaluate (List contextNodes, Object arg, Navigator nav) 95 { 96 if (contextNodes.size() == 0) 97 return Collections.EMPTY_LIST; 98 99 List nodes = new ArrayList(); 100 101 Object contextNode = contextNodes.get(0); 102 103 if (arg instanceof List) { 104 Iterator iter = ((List)arg).iterator(); 105 while (iter.hasNext()) { 106 String id = StringFunction.evaluate(iter.next(), nav); 107 nodes.addAll( evaluate( contextNodes, id, nav ) ); 108 } 109 } else { 110 String ids = StringFunction.evaluate(arg, nav); 111 StringTokenizer tok = new StringTokenizer(ids, " \t\n\r"); 112 while (tok.hasMoreTokens()) { 113 String id = tok.nextToken(); 114 Object node = nav.getElementById(contextNode, id); 115 if (node != null) { 116 nodes.add(node); 117 } 118 } 119 } 120 return nodes; 121 } 122 } 123