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1   /*
2    * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/expr/DefaultLocationPath.java,v 1.24 2005/04/06 09:09:19 elharo Exp $
3    * $Revision: 1.24 $
4    * $Date: 2005/04/06 09:09:19 $
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: DefaultLocationPath.java,v 1.24 2005/04/06 09:09:19 elharo Exp $
60   */
61  package org.jaxen.expr;
62  
63  import java.util.ArrayList;
64  import java.util.Collections;
65  import java.util.Iterator;
66  import java.util.LinkedList;
67  import java.util.List;
68  
69  import org.jaxen.Context;
70  import org.jaxen.ContextSupport;
71  import org.jaxen.JaxenException;
72  
73  abstract class DefaultLocationPath extends DefaultExpr implements LocationPath
74  {
75      private List steps;
76      
77      public DefaultLocationPath()
78      {
79          this.steps = new LinkedList();
80      }
81  
82      public void addStep(Step step)
83      {
84          getSteps().add(step);
85      }
86  
87      public List getSteps()
88      {
89          return this.steps;
90      }
91  
92      public Expr simplify()
93      {
94          Iterator stepIter = getSteps().iterator();
95          Step eachStep = null;
96          while (stepIter.hasNext())
97          {
98              eachStep = (Step) stepIter.next();
99              eachStep.simplify();
100         }
101         return this;
102     }
103 
104     public String getText()
105     {
106         StringBuffer buf = new StringBuffer();
107         Iterator stepIter = getSteps().iterator();
108         while (stepIter.hasNext())
109         {
110             buf.append(((Step) stepIter.next()).getText());
111             if (stepIter.hasNext())
112             {
113                 buf.append("/");
114             }
115         }
116         return buf.toString();
117     }
118 
119     public String toString()
120     {
121         StringBuffer buf = new StringBuffer();
122         Iterator stepIter = getSteps().iterator();
123         while (stepIter.hasNext())
124         {
125             buf.append(stepIter.next().toString());
126             if (stepIter.hasNext())
127             {
128                 buf.append("/");
129             }
130         }
131         return buf.toString();
132     }
133 
134     public boolean isAbsolute()
135     {
136         return false;
137     }
138 
139     public Object evaluate(Context context) throws JaxenException
140     {
141         List nodeSet = context.getNodeSet();
142         List contextNodeSet = new ArrayList(nodeSet.size());
143         contextNodeSet.addAll(nodeSet);
144         ContextSupport support = context.getContextSupport();
145         Context stepContext = new Context(support);
146         Iterator stepIter = getSteps().iterator();
147         while ( stepIter.hasNext() )
148         {
149             Step eachStep = (Step) stepIter.next();
150             stepContext.setNodeSet(contextNodeSet);
151             contextNodeSet = eachStep.evaluate(stepContext);
152             // now we need to reverse the list if this is a reverse axis
153             // ???? should create an isReverseAxis method in Step to handle this
154             int axis = eachStep.getAxis();
155             if (axis == org.jaxen.saxpath.Axis.PRECEDING
156               || axis == org.jaxen.saxpath.Axis.PRECEDING_SIBLING
157               || axis == org.jaxen.saxpath.Axis.ANCESTOR
158               || axis == org.jaxen.saxpath.Axis.ANCESTOR_OR_SELF) {
159                 Collections.reverse(contextNodeSet);
160             }
161         }
162         
163         if (getSteps().size() > 1) {
164             Collections.sort(contextNodeSet, new NodeComparator(support.getNavigator()));
165         }
166         
167         return contextNodeSet;
168     }
169 
170 }
171