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1   /*
2    * Licensed to the Apache Software Foundation (ASF) under one or more
3    * contributor license agreements.  See the NOTICE file distributed with
4    * this work for additional information regarding copyright ownership.
5    * The ASF licenses this file to You under the Apache License, Version 2.0
6    * (the "License"); you may not use this file except in compliance with
7    * the License.  You may obtain a copy of the License at
8    *
9    *      http://www.apache.org/licenses/LICENSE-2.0
10   *
11   * Unless required by applicable law or agreed to in writing, software
12   * distributed under the License is distributed on an "AS IS" BASIS,
13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14   * See the License for the specific language governing permissions and
15   * limitations under the License.
16   */
17   /* Generated By:JavaCC: Do not edit this line. ParseException.java Version 3.0 */
18  package org.apache.commons.jexl.parser;
19  
20  /**
21   * This exception is thrown when parse errors are encountered.
22   * You can explicitly create objects of this exception type by
23   * calling the method generateParseException in the generated
24   * parser.
25   *
26   * You can modify this class to customize your error reporting
27   * mechanisms so long as you retain the public fields.
28   */
29  public class ParseException extends Exception {
30  
31    /**
32     * This constructor is used by the method "generateParseException"
33     * in the generated parser.  Calling this constructor generates
34     * a new object of this type with the fields "currentToken",
35     * "expectedTokenSequences", and "tokenImage" set.  The boolean
36     * flag "specialConstructor" is also set to true to indicate that
37     * this constructor was used to create this object.
38     * This constructor calls its super class with the empty string
39     * to force the "toString" method of parent class "Throwable" to
40     * print the error message in the form:
41     *     ParseException: <result of getMessage>
42     */
43    public ParseException(Token currentTokenVal,
44                          int[][] expectedTokenSequencesVal,
45                          String[] tokenImageVal
46                         )
47    {
48      super("");
49      specialConstructor = true;
50      currentToken = currentTokenVal;
51      expectedTokenSequences = expectedTokenSequencesVal;
52      tokenImage = tokenImageVal;
53    }
54  
55    /**
56     * The following constructors are for use by you for whatever
57     * purpose you can think of.  Constructing the exception in this
58     * manner makes the exception behave in the normal way - i.e., as
59     * documented in the class "Throwable".  The fields "errorToken",
60     * "expectedTokenSequences", and "tokenImage" do not contain
61     * relevant information.  The JavaCC generated code does not use
62     * these constructors.
63     */
64  
65    public ParseException() {
66      super();
67      specialConstructor = false;
68    }
69  
70    public ParseException(String message) {
71      super(message);
72      specialConstructor = false;
73    }
74  
75    /**
76     * This variable determines which constructor was used to create
77     * this object and thereby affects the semantics of the
78     * "getMessage" method (see below).
79     */
80    protected boolean specialConstructor;
81  
82    /**
83     * This is the last token that has been consumed successfully.  If
84     * this object has been created due to a parse error, the token
85     * followng this token will (therefore) be the first error token.
86     */
87    public Token currentToken;
88  
89    /**
90     * Each entry in this array is an array of integers.  Each array
91     * of integers represents a sequence of tokens (by their ordinal
92     * values) that is expected at this point of the parse.
93     */
94    public int[][] expectedTokenSequences;
95  
96    /**
97     * This is a reference to the "tokenImage" array of the generated
98     * parser within which the parse error occurred.  This array is
99     * defined in the generated ...Constants interface.
100    */
101   public String[] tokenImage;
102 
103   /**
104    * This method has the standard behavior when this object has been
105    * created using the standard constructors.  Otherwise, it uses
106    * "currentToken" and "expectedTokenSequences" to generate a parse
107    * error message and returns it.  If this object has been created
108    * due to a parse error, and you do not catch it (it gets thrown
109    * from the parser), then this method is called during the printing
110    * of the final stack trace, and hence the correct error message
111    * gets displayed.
112    */
113   public String getMessage() {
114     if (!specialConstructor) {
115       return super.getMessage();
116     }
117     StringBuffer expected = new StringBuffer();
118     int maxSize = 0;
119     for (int i = 0; i < expectedTokenSequences.length; i++) {
120       if (maxSize < expectedTokenSequences[i].length) {
121         maxSize = expectedTokenSequences[i].length;
122       }
123       for (int j = 0; j < expectedTokenSequences[i].length; j++) {
124         expected.append(tokenImage[expectedTokenSequences[i][j]]).append(" ");
125       }
126       if (expectedTokenSequences[i][expectedTokenSequences[i].length - 1] != 0) {
127         expected.append("...");
128       }
129       expected.append(eol).append("    ");
130     }
131     String retval = "Encountered \"";
132     Token tok = currentToken.next;
133     for (int i = 0; i < maxSize; i++) {
134       if (i != 0) retval += " ";
135       if (tok.kind == 0) {
136         retval += tokenImage[0];
137         break;
138       }
139       retval += add_escapes(tok.image);
140       tok = tok.next;
141     }
142     retval += "\" at line " + currentToken.next.beginLine + ", column " + currentToken.next.beginColumn;
143     retval += "." + eol;
144     if (expectedTokenSequences.length == 1) {
145       retval += "Was expecting:" + eol + "    ";
146     } else {
147       retval += "Was expecting one of:" + eol + "    ";
148     }
149     retval += expected.toString();
150     return retval;
151   }
152 
153   /**
154    * The end of line string for this machine.
155    */
156   protected String eol = System.getProperty("line.separator", "\n");
157 
158   /**
159    * Used to convert raw characters to their escaped version
160    * when these raw version cannot be used as part of an ASCII
161    * string literal.
162    */
163   protected String add_escapes(String str) {
164       StringBuffer retval = new StringBuffer();
165       char ch;
166       for (int i = 0; i < str.length(); i++) {
167         switch (str.charAt(i))
168         {
169            case 0 :
170               continue;
171            case '\b':
172               retval.append("\\b");
173               continue;
174            case '\t':
175               retval.append("\\t");
176               continue;
177            case '\n':
178               retval.append("\\n");
179               continue;
180            case '\f':
181               retval.append("\\f");
182               continue;
183            case '\r':
184               retval.append("\\r");
185               continue;
186            case '\"':
187               retval.append("\\\"");
188               continue;
189            case '\'':
190               retval.append("\\\'");
191               continue;
192            case '\\':
193               retval.append("\\\\");
194               continue;
195            default:
196               if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
197                  String s = "0000" + Integer.toString(ch, 16);
198                  retval.append("\\u" + s.substring(s.length() - 4, s.length()));
199               } else {
200                  retval.append(ch);
201               }
202               continue;
203         }
204       }
205       return retval.toString();
206    }
207 
208 }