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1   /*
2    * $Header: /home/projects/jaxen/scm/jaxen/src/java/main/org/jaxen/saxpath/XPathSyntaxException.java,v 1.6 2005/06/14 15:06:22 elharo Exp $
3    * $Revision: 1.6 $
4    * $Date: 2005/06/14 15:06:22 $
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 2005/06/14 15:06:22 elharo Exp $
60   */
61  
62  package org.jaxen.saxpath;
63  
64  
65  /***
66   * Represents a syntax error in an XPath expression.
67   * This is a compile-time error that is detectable irrespective of 
68   * the context in which the XPath expression is evaluated.
69   */
70  public class XPathSyntaxException extends SAXPathException
71  {
72      private String xpath;
73      private int    position;
74      private final static String lineSeparator = System.getProperty("line.separator");
75  
76      /***
77       * Creates a new XPathSyntaxException.
78       * 
79       * @param xpath the incorrect XPath expression 
80       * @param position the index of the character at which the syntax error was detected
81       * @param message the detail message
82       */
83      public XPathSyntaxException(String xpath,
84                                  int position,
85                                  String message)
86      {
87          super( message );
88          this.position = position;
89          this.xpath    = xpath;
90      }
91  
92      /***
93       * <p>
94       * Returns the index of the character at which the syntax error was detected
95       * in the XPath expression.
96       * </p>
97       * 
98       * @return the character index in the XPath expression  
99       *     at which the syntax error was detected
100      */
101     public int getPosition()
102     {
103         return this.position;
104     }
105 
106     /***
107      * <p>
108      * Returns the syntactically incorrect XPath expression.
109      * </p>
110      * 
111      * @return the syntactically incorrect XPath expression
112      */
113     public String getXPath()
114     {
115         return this.xpath;
116     }
117 
118     public String toString()
119     {
120         return getClass() + ": " + getXPath() + ": " + getPosition() + ": " + getMessage();
121     }
122 
123     /***
124      * <p>
125      * Returns a string in the form <code>"   ^"</code> which, when placed on the line
126      * below the XPath expression in a monospaced font, should point to the
127      * location of the error.
128      * </p>
129      * 
130      * @return the position marker 
131      */
132     public String getPositionMarker()
133     {
134         int pos = getPosition();
135         StringBuffer buf = new StringBuffer(pos+1);
136         for ( int i = 0 ; i < pos ; ++i )
137         {
138             buf.append(" ");
139         }
140 
141         buf.append("^");
142 
143         return buf.toString();
144         
145     }
146 
147     /***
148      * <p>
149      * Returns a long formatted description of the error,
150      * including line breaks.
151      * </p>
152      * 
153      * @return a longer description of the error on multiple lines
154      */
155     public String getMultilineMessage()
156     {
157         StringBuffer buf = new StringBuffer();
158 
159         buf.append( getMessage() );
160         buf.append( lineSeparator );
161         buf.append( getXPath() );
162         buf.append( lineSeparator );
163 
164         buf.append( getPositionMarker() );
165 
166         return buf.toString();
167     }
168 
169 }