Coverage Report - org.jaxen.function.IdFunction

Classes in this File Line Coverage Branch Coverage Complexity
IdFunction
100% 
100% 
4

 1  
 /*
 2  
  * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/function/IdFunction.java,v 1.12 2005/09/23 13:58:46 elharo Exp $
 3  
  * $Revision: 1.12 $
 4  
  * $Date: 2005/09/23 13:58:46 $
 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 1.12 2005/09/23 13:58:46 elharo 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> </p>
 77  
  *  
 78  
  * <p>The <b>id</b> function returns a <code>List</code>
 79  
  * of all the elements in the context document that have an ID
 80  
  * matching one of a specified list of IDs. How an attribute is determined
 81  
  * to be of type ID depends on the navigator, but it normally requires that
 82  
  * the attribute be declared to have type ID in the DTD. 
 83  
  * </p>
 84  
  * 
 85  
  * <p>
 86  
  * There should be no more than one element in any document with a 
 87  
  * certain ID. However, if there are multiple such elements--i.e. if 
 88  
  * there are duplicate IDs--then this function selects only the first element 
 89  
  * in document order with the specified ID. 
 90  
  * </p>
 91  
  * 
 92  
  * @author Erwin Bolwidt (ejb @ klomp.org)
 93  
  * @author J\u00e9r\u00f4me N\u00e8gre (jerome.negre @ e-xmlmedia.fr)
 94  
  * 
 95  
  * @see <a href="http://www.w3.org/TR/xpath#function-id" target="_top">Section 4.1 of the XPath Specification</a>
 96  
  */
 97  
 public class IdFunction implements Function
 98  
 {
 99  
 
 100  
     /**
 101  
      * Create a new <code>IdFunction</code> object.
 102  
      */
 103  294
     public IdFunction() {}
 104  
     
 105  
     /** 
 106  
      * Returns a list of the nodes with the specified IDs.
 107  
      *
 108  
      * @param context the context at the point in the
 109  
      *         expression when the function is called
 110  
      * @param args a list with exactly one item which is either a string
 111  
      *     a node-set
 112  
      * 
 113  
      * @return a <code>List</code> containing the first node in document 
 114  
      *     with each of the specified IDs; or 
 115  
      *     an empty list if there are no such nodes
 116  
      * 
 117  
      * @throws FunctionCallException if <code>args</code> has more or less than one item
 118  
      */
 119  
     public Object call(Context context, List args) throws FunctionCallException
 120  
     {
 121  42
         if ( args.size() == 1 ) {
 122  30
             return evaluate( context.getNodeSet(),
 123  
                              args.get(0), context.getNavigator() );
 124  
         }
 125  
 
 126  12
         throw new FunctionCallException( "id() requires one argument" );
 127  
     }
 128  
 
 129  
     /** 
 130  
      * Returns a list of the nodes with the specified IDs.
 131  
      * 
 132  
      * @param contextNodes the context node-set. The first item in this list
 133  
      *     determines the document in which the search is performed.
 134  
      * @param arg the ID or IDs to search for
 135  
      * @param nav the navigator used to calculate string-values and search
 136  
      *     by ID
 137  
      * 
 138  
      * @return a <code>List</code> containing the first node in document 
 139  
      *     with each of the specified IDs; or 
 140  
      *     an empty list if there are no such nodes
 141  
      * 
 142  
      */
 143  
     public static List evaluate(List contextNodes, Object arg, Navigator nav)
 144  
     {
 145  48
         if (contextNodes.size() == 0) return Collections.EMPTY_LIST;
 146  
       
 147  48
         List nodes = new ArrayList();
 148  
 
 149  48
         Object contextNode = contextNodes.get(0);
 150  
 
 151  48
         if (arg instanceof List) {
 152  6
             Iterator iter = ((List)arg).iterator();
 153  24
             while (iter.hasNext()) {
 154  18
                 String id = StringFunction.evaluate(iter.next(), nav);
 155  18
                 nodes.addAll( evaluate( contextNodes, id, nav ) );
 156  
             }
 157  
         } 
 158  
         else {
 159  42
             String ids = StringFunction.evaluate(arg, nav);
 160  42
             StringTokenizer tok = new StringTokenizer(ids, " \t\n\r");
 161  84
             while (tok.hasMoreTokens()) {
 162  42
                 String id = tok.nextToken();
 163  42
                 Object node = nav.getElementById(contextNode, id);
 164  42
                 if (node != null) {
 165  24
                     nodes.add(node);
 166  
                 }
 167  
             }
 168  
         }
 169  48
         return nodes;
 170  
     }
 171  
     
 172  
 }
 173