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1   /*
2    * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/XPathSyntaxException.java,v 1.6 2004/09/16 21:05:25 bewins Exp $
3    * $Revision: 1.6 $
4    * $Date: 2004/09/16 21:05:25 $
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: XPathSyntaxException.java,v 1.6 2004/09/16 21:05:25 bewins Exp $
60   */
61  
62  
63  package org.jaxen;
64  
65  /*** Indicates an error during parsing of an XPath
66   *  expression.
67   *
68   *  @see XPath
69   *
70   *  @author <a href="mailto:bob@werken.com">bob mcwhirter</a>
71   *  @author <a href="mailto:jstrachan@apache.org">James Strachan</a>
72   */
73  public class XPathSyntaxException extends JaxenException
74  {
75      /*** The textual xpath expression. */
76      private String xpath;
77  
78      /*** The position of the error. */
79      private int    position;
80  
81      public XPathSyntaxException(org.jaxen.saxpath.XPathSyntaxException e)
82      {
83          super( e );
84  
85          this.xpath    = e.getXPath();
86          this.position = e.getPosition();
87      }
88  
89      /*** Construct.
90       *
91       *  @param xpath The erroneous xpath.
92       *  @param position The position of the error.
93       *  @param message The error message.
94       */
95      public XPathSyntaxException(String xpath,
96                                  int position,
97                                  String message)
98      {
99          super( message );
100 
101         this.xpath    = xpath;
102         this.position = position;
103     }
104 
105     /*** Retrieve the position of the error.
106      *
107      *  @return The position of the error.
108      */
109     public int getPosition()
110     {
111         return this.position;
112     }
113 
114     /*** Retrieve the expression containing the error.
115      *
116      *  @return The erroneous expression.
117      */
118     public String getXPath()
119     {
120         return this.xpath;
121     }
122 
123     /*** Retrieve a string useful for denoting where
124      *  the error occured.
125      *
126      *  <p>
127      *  This is a string composed of whitespace and
128      *  a marker at the position (see {@link #getPosition})
129      *  of the error.  This is useful for creating
130      *  friendly multi-line error displays.
131      *  </p>
132      *
133      *  @return The error position marker.
134      */
135     public String getPositionMarker()
136     {
137         StringBuffer buf = new StringBuffer();
138 
139         int pos = getPosition();
140 
141         for ( int i = 0 ; i < pos ; ++i )
142         {
143             buf.append(" ");
144         }
145 
146         buf.append("^");
147 
148         return buf.toString();
149         
150     }
151 
152     /*** Retrieve the friendly multi-line error message.
153      *
154      *  <p>
155      *  This returns a multi-line string that contains
156      *  the original erroneous xpath expression with a
157      *  marker underneath indicating exactly where the
158      *  error occurred.
159      *  </p>
160      *
161      *  @return The multi-line error message.
162      */
163     public String getMultilineMessage()
164     {
165         StringBuffer buf = new StringBuffer();
166 
167         buf.append( getMessage() );
168         buf.append( "\n" );
169         buf.append( getXPath() );
170         buf.append( "\n" );
171 
172         buf.append( getPositionMarker() );
173 
174         return buf.toString();
175     }
176 }