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      1 /* Generated By:JavaCC: Do not edit this line. ParseException.java Version 3.0 */
      2 /*
      3  *  Copyright 2004 the mime4j project
      4  *
      5  *  Licensed under the Apache License, Version 2.0 (the "License");
      6  *  you may not use this file except in compliance with the License.
      7  *  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 package org.apache.james.mime4j.field.contenttype.parser;
     18 
     19 /**
     20  * This exception is thrown when parse errors are encountered.
     21  * You can explicitly create objects of this exception type by
     22  * calling the method generateParseException in the generated
     23  * parser.
     24  *
     25  * You can modify this class to customize your error reporting
     26  * mechanisms so long as you retain the public fields.
     27  */
     28 public class ParseException extends Exception {
     29 
     30   /**
     31    * This constructor is used by the method "generateParseException"
     32    * in the generated parser.  Calling this constructor generates
     33    * a new object of this type with the fields "currentToken",
     34    * "expectedTokenSequences", and "tokenImage" set.  The boolean
     35    * flag "specialConstructor" is also set to true to indicate that
     36    * this constructor was used to create this object.
     37    * This constructor calls its super class with the empty string
     38    * to force the "toString" method of parent class "Throwable" to
     39    * print the error message in the form:
     40    *     ParseException: <result of getMessage>
     41    */
     42   public ParseException(Token currentTokenVal,
     43                         int[][] expectedTokenSequencesVal,
     44                         String[] tokenImageVal
     45                        )
     46   {
     47     super("");
     48     specialConstructor = true;
     49     currentToken = currentTokenVal;
     50     expectedTokenSequences = expectedTokenSequencesVal;
     51     tokenImage = tokenImageVal;
     52   }
     53 
     54   /**
     55    * The following constructors are for use by you for whatever
     56    * purpose you can think of.  Constructing the exception in this
     57    * manner makes the exception behave in the normal way - i.e., as
     58    * documented in the class "Throwable".  The fields "errorToken",
     59    * "expectedTokenSequences", and "tokenImage" do not contain
     60    * relevant information.  The JavaCC generated code does not use
     61    * these constructors.
     62    */
     63 
     64   public ParseException() {
     65     super();
     66     specialConstructor = false;
     67   }
     68 
     69   public ParseException(String message) {
     70     super(message);
     71     specialConstructor = false;
     72   }
     73 
     74   /**
     75    * This variable determines which constructor was used to create
     76    * this object and thereby affects the semantics of the
     77    * "getMessage" method (see below).
     78    */
     79   protected boolean specialConstructor;
     80 
     81   /**
     82    * This is the last token that has been consumed successfully.  If
     83    * this object has been created due to a parse error, the token
     84    * followng this token will (therefore) be the first error token.
     85    */
     86   public Token currentToken;
     87 
     88   /**
     89    * Each entry in this array is an array of integers.  Each array
     90    * of integers represents a sequence of tokens (by their ordinal
     91    * values) that is expected at this point of the parse.
     92    */
     93   public int[][] expectedTokenSequences;
     94 
     95   /**
     96    * This is a reference to the "tokenImage" array of the generated
     97    * parser within which the parse error occurred.  This array is
     98    * defined in the generated ...Constants interface.
     99    */
    100   public String[] tokenImage;
    101 
    102   /**
    103    * This method has the standard behavior when this object has been
    104    * created using the standard constructors.  Otherwise, it uses
    105    * "currentToken" and "expectedTokenSequences" to generate a parse
    106    * error message and returns it.  If this object has been created
    107    * due to a parse error, and you do not catch it (it gets thrown
    108    * from the parser), then this method is called during the printing
    109    * of the final stack trace, and hence the correct error message
    110    * gets displayed.
    111    */
    112   public String getMessage() {
    113     if (!specialConstructor) {
    114       return super.getMessage();
    115     }
    116     StringBuffer expected = new StringBuffer();
    117     int maxSize = 0;
    118     for (int i = 0; i < expectedTokenSequences.length; i++) {
    119       if (maxSize < expectedTokenSequences[i].length) {
    120         maxSize = expectedTokenSequences[i].length;
    121       }
    122       for (int j = 0; j < expectedTokenSequences[i].length; j++) {
    123         expected.append(tokenImage[expectedTokenSequences[i][j]]).append(" ");
    124       }
    125       if (expectedTokenSequences[i][expectedTokenSequences[i].length - 1] != 0) {
    126         expected.append("...");
    127       }
    128       expected.append(eol).append("    ");
    129     }
    130     String retval = "Encountered \"";
    131     Token tok = currentToken.next;
    132     for (int i = 0; i < maxSize; i++) {
    133       if (i != 0) retval += " ";
    134       if (tok.kind == 0) {
    135         retval += tokenImage[0];
    136         break;
    137       }
    138       retval += add_escapes(tok.image);
    139       tok = tok.next;
    140     }
    141     retval += "\" at line " + currentToken.next.beginLine + ", column " + currentToken.next.beginColumn;
    142     retval += "." + eol;
    143     if (expectedTokenSequences.length == 1) {
    144       retval += "Was expecting:" + eol + "    ";
    145     } else {
    146       retval += "Was expecting one of:" + eol + "    ";
    147     }
    148     retval += expected.toString();
    149     return retval;
    150   }
    151 
    152   /**
    153    * The end of line string for this machine.
    154    */
    155   protected String eol = System.getProperty("line.separator", "\n");
    156 
    157   /**
    158    * Used to convert raw characters to their escaped version
    159    * when these raw version cannot be used as part of an ASCII
    160    * string literal.
    161    */
    162   protected String add_escapes(String str) {
    163       StringBuffer retval = new StringBuffer();
    164       char ch;
    165       for (int i = 0; i < str.length(); i++) {
    166         switch (str.charAt(i))
    167         {
    168            case 0 :
    169               continue;
    170            case '\b':
    171               retval.append("\\b");
    172               continue;
    173            case '\t':
    174               retval.append("\\t");
    175               continue;
    176            case '\n':
    177               retval.append("\\n");
    178               continue;
    179            case '\f':
    180               retval.append("\\f");
    181               continue;
    182            case '\r':
    183               retval.append("\\r");
    184               continue;
    185            case '\"':
    186               retval.append("\\\"");
    187               continue;
    188            case '\'':
    189               retval.append("\\\'");
    190               continue;
    191            case '\\':
    192               retval.append("\\\\");
    193               continue;
    194            default:
    195               if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
    196                  String s = "0000" + Integer.toString(ch, 16);
    197                  retval.append("\\u" + s.substring(s.length() - 4, s.length()));
    198               } else {
    199                  retval.append(ch);
    200               }
    201               continue;
    202         }
    203       }
    204       return retval.toString();
    205    }
    206 
    207 }
    208