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1   /*
2    * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/saxpath/Axis.java,v 1.5 2005/06/14 14:55:30 elharo Exp $
3    * $Revision: 1.5 $
4    * $Date: 2005/06/14 14:55:30 $
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: Axis.java,v 1.5 2005/06/14 14:55:30 elharo Exp $
60   */
61  
62  
63  
64  package org.jaxen.saxpath;
65  
66  import org.jaxen.JaxenRuntimeException;
67  
68  
69  
70  /***
71   * 
72   * Internal SAXPath class that contains constants representing 
73   * XPath operators to avoid a lot of string comparisons. 
74   */
75  public class Axis
76  {
77      
78      private Axis() {}
79      
80      // XXX Ultimately these should use the type-safe enum pattern instead
81      /*** Marker for an invalid axis */
82      public final static int INVALID_AXIS       =  0;
83  
84      /*** The <code>child</code> axis */
85      public final static int CHILD              =  1;
86  
87      /*** The <code>descendant</code> axis */
88      public final static int DESCENDANT         =  2;
89  
90      /*** The <code>parent</code> axis */
91      public final static int PARENT             =  3;
92  
93      /*** The <code>ancestor</code> axis */
94      public final static int ANCESTOR           =  4;
95  
96      /*** The <code>following-sibling</code> axis */
97      public final static int FOLLOWING_SIBLING  =  5;
98  
99      /*** The <code>preceding-sibling</code> axis */
100     public final static int PRECEDING_SIBLING  =  6;
101 
102     /*** The <code>following</code> axis */
103     public final static int FOLLOWING          =  7;
104 
105     /*** The <code>preceding</code> axis */
106     public final static int PRECEDING          =  8;
107 
108     /*** The <code>attribute</code> axis */
109     public final static int ATTRIBUTE          =  9;
110 
111     /*** The <code>namespace</code> axis */
112     public final static int NAMESPACE          = 10;
113 
114     /*** The <code>self</code> axis */
115     public final static int SELF               = 11;
116 
117     /*** The <code>descendant-or-self</code> axis */
118     public final static int DESCENDANT_OR_SELF = 12;
119 
120     /*** The <code>ancestor-or-self</code> axis */
121     public final static int ANCESTOR_OR_SELF   = 13;
122 
123     /***
124      * <p>
125      * Returns the name of the axis.
126      * </p>
127      * 
128      * @param axisNum the axis code
129      * @return the name of the axis such as might be used in an XPath expression
130      * @throws JaxenRuntimeException if the number does not represent one of the 13
131      *     XPath axes
132      */
133     public static String lookup(int axisNum)
134     {
135         switch ( axisNum )
136         {
137             case CHILD:
138                 return "child";
139 
140             case DESCENDANT:
141                 return "descendant";
142 
143             case PARENT:
144                 return "parent";
145 
146             case ANCESTOR:
147                 return "ancestor";
148 
149             case FOLLOWING_SIBLING:
150                 return "following-sibling";
151 
152             case PRECEDING_SIBLING:
153                 return "preceding-sibling";
154 
155             case FOLLOWING:
156                 return "following";
157 
158             case PRECEDING:
159                 return "preceding";
160 
161             case ATTRIBUTE:
162                 return "attribute";
163 
164             case NAMESPACE:
165                 return "namespace";
166 
167             case SELF:
168                 return "self";
169 
170             case DESCENDANT_OR_SELF:
171                 return "descendant-or-self";
172 
173             case ANCESTOR_OR_SELF:
174                 return "ancestor-or-self";
175         }
176 
177         throw new JaxenRuntimeException("Illegal Axis Number");
178     }
179 
180     /***
181      * <p>
182      * Returns the code for an axis given its name.
183      * </p>
184      * 
185      * @param axisName the name of the axis: child, parent, descendant, descendant-or-self, etc.
186      * @return the axis code
187      */
188     public static int lookup(String axisName)
189     {
190         if ( "child".equals( axisName ) )
191         {
192             return CHILD;
193         }
194 
195         if ( "descendant".equals( axisName ) )
196         {
197             return DESCENDANT;
198         }
199 
200         if ( "parent".equals( axisName ) )
201         {
202             return PARENT;
203         }
204 
205         if ( "ancestor".equals( axisName ) )
206         {
207             return ANCESTOR;
208         }
209 
210         if ( "following-sibling".equals( axisName ) )
211         {
212             return FOLLOWING_SIBLING;
213         }
214 
215         if ( "preceding-sibling".equals( axisName ) )
216         {
217             return PRECEDING_SIBLING;
218         }
219 
220         if ( "following".equals( axisName ) )
221         {
222             return FOLLOWING;
223         }
224 
225         if ( "preceding".equals( axisName ) )
226         {
227             return PRECEDING;
228         }
229 
230         if ( "attribute".equals( axisName ) )
231         {
232             return ATTRIBUTE;
233         }
234 
235         if ( "namespace".equals( axisName ) )
236         {
237             return NAMESPACE;
238         }
239 
240         if ( "self".equals( axisName ) )
241         {
242             return SELF;
243         }
244 
245         if ( "descendant-or-self".equals( axisName ) )
246         {
247             return DESCENDANT_OR_SELF;
248         }
249 
250         if ( "ancestor-or-self".equals( axisName ) )
251         {
252             return ANCESTOR_OR_SELF;
253         }
254 
255         return INVALID_AXIS;
256     }
257 }