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1   /* Generated By:JavaCC: Do not edit this line. ParseException.java Version 3.0 */
2   
3   /***************************************************************************************
4    * Copyright (c) Jonas BonŽr, Alexandre Vasseur. All rights reserved.                 *
5    * http://aspectwerkz.codehaus.org                                                    *
6    * ---------------------------------------------------------------------------------- *
7    * The software in this package is published under the terms of the LGPL license      *
8    * a copy of which has been included with this distribution in the license.txt file.  *
9    **************************************************************************************/
10  package org.codehaus.aspectwerkz.annotation.expression.ast;
11  
12  /***
13   * This exception is thrown when parse errors are encountered. You can explicitly create objects of this exception type
14   * by calling the method generateParseException in the generated parser. <p/>You can modify this class to customize your
15   * error reporting mechanisms so long as you retain the public fields.
16   */
17  public class ParseException extends Exception {
18      /***
19       * This variable determines which constructor was used to create this object and thereby affects the semantics of
20       * the "getMessage" method (see below).
21       */
22      protected boolean specialConstructor;
23  
24      /***
25       * This is the last token that has been consumed successfully. If this object has been created due to a parse error,
26       * the token followng this token will (therefore) be the first error token.
27       */
28      public Token currentToken;
29  
30      /***
31       * Each entry in this array is an array of integers. Each array of integers represents a sequence of tokens (by
32       * their ordinal values) that is expected at this point of the parse.
33       */
34      public int[][] expectedTokenSequences;
35  
36      /***
37       * This is a reference to the "tokenImage" array of the generated parser within which the parse error occurred. This
38       * array is defined in the generated ...Constants interface.
39       */
40      public String[] tokenImage;
41  
42      /***
43       * The end of line string for this machine.
44       */
45      protected String eol = System.getProperty("line.separator", "\n");
46  
47      /***
48       * This constructor is used by the method "generateParseException" in the generated parser. Calling this constructor
49       * generates a new object of this type with the fields "currentToken", "expectedTokenSequences", and "tokenImage"
50       * set. The boolean flag "specialConstructor" is also set to true to indicate that this constructor was used to
51       * create this object. This constructor calls its super class with the empty string to force the "toString" method
52       * of parent class "Throwable" to print the error message in the form: ParseException: <result of getMessage>
53       */
54      public ParseException(Token currentTokenVal, int[][] expectedTokenSequencesVal, String[] tokenImageVal) {
55          super("");
56          specialConstructor = true;
57          currentToken = currentTokenVal;
58          expectedTokenSequences = expectedTokenSequencesVal;
59          tokenImage = tokenImageVal;
60      }
61  
62      /***
63       * The following constructors are for use by you for whatever purpose you can think of. Constructing the exception
64       * in this manner makes the exception behave in the normal way - i.e., as documented in the class "Throwable". The
65       * fields "errorToken", "expectedTokenSequences", and "tokenImage" do not contain relevant information. The JavaCC
66       * generated code does not use these constructors.
67       */
68      public ParseException() {
69          super();
70          specialConstructor = false;
71      }
72  
73      public ParseException(String message) {
74          super(message);
75          specialConstructor = false;
76      }
77  
78      /***
79       * This method has the standard behavior when this object has been created using the standard constructors.
80       * Otherwise, it uses "currentToken" and "expectedTokenSequences" to generate a parse error message and returns it.
81       * If this object has been created due to a parse error, and you do not catch it (it gets thrown from the parser),
82       * then this method is called during the printing of the final stack trace, and hence the correct error message gets
83       * displayed.
84       */
85      public String getMessage() {
86          if (!specialConstructor) {
87              return super.getMessage();
88          }
89          String expected = "";
90          int maxSize = 0;
91          for (int i = 0; i < expectedTokenSequences.length; i++) {
92              if (maxSize < expectedTokenSequences[i].length) {
93                  maxSize = expectedTokenSequences[i].length;
94              }
95              for (int j = 0; j < expectedTokenSequences[i].length; j++) {
96                  expected += (tokenImage[expectedTokenSequences[i][j]] + " ");
97              }
98              if (expectedTokenSequences[i][expectedTokenSequences[i].length - 1] != 0) {
99                  expected += "...";
100             }
101             expected += (eol + "    ");
102         }
103         String retval = "Encountered \"";
104         Token tok = currentToken.next;
105         for (int i = 0; i < maxSize; i++) {
106             if (i != 0) {
107                 retval += " ";
108             }
109             if (tok.kind == 0) {
110                 retval += tokenImage[0];
111                 break;
112             }
113             retval += add_escapes(tok.image);
114             tok = tok.next;
115         }
116         retval += ("\" at line " + currentToken.next.beginLine + ", column " + currentToken.next.beginColumn);
117         retval += ("." + eol);
118         if (expectedTokenSequences.length == 1) {
119             retval += ("Was expecting:" + eol + "    ");
120         } else {
121             retval += ("Was expecting one of:" + eol + "    ");
122         }
123         retval += expected;
124         return retval;
125     }
126 
127     /***
128      * Used to convert raw characters to their escaped version when these raw version cannot be used as part of an ASCII
129      * string literal.
130      */
131     protected String add_escapes(String str) {
132         StringBuffer retval = new StringBuffer();
133         char ch;
134         for (int i = 0; i < str.length(); i++) {
135             switch (str.charAt(i)) {
136                 case 0:
137                     continue;
138                 case '\b':
139                     retval.append("//b");
140                     continue;
141                 case '\t':
142                     retval.append("//t");
143                     continue;
144                 case '\n':
145                     retval.append("//n");
146                     continue;
147                 case '\f':
148                     retval.append("//f");
149                     continue;
150                 case '\r':
151                     retval.append("//r");
152                     continue;
153                 case '\"':
154                     retval.append("//\"");
155                     continue;
156                 case '\'':
157                     retval.append("//\'");
158                     continue;
159                 case '//':
160                     retval.append("////");
161                     continue;
162                 default:
163                     if (((ch = str.charAt(i)) < 0x20) || (ch > 0x7e)) {
164                         String s = "0000" + Integer.toString(ch, 16);
165                         retval.append("//u" + s.substring(s.length() - 4, s.length()));
166                     } else {
167                         retval.append(ch);
168                     }
169                     continue;
170             }
171         }
172         return retval.toString();
173     }
174 }