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    1   /*
    2    * Copyright 2002-2006 The Apache Software Foundation.
    3    *
    4    * Licensed under the Apache License, Version 2.0 (the "License");
    5    * you may not use this file except in compliance with the License.
    6    * You may obtain a copy of the License at
    7    *
    8    *      http://www.apache.org/licenses/LICENSE-2.0
    9    *
    10   * Unless required by applicable law or agreed to in writing, software
    11   * distributed under the License is distributed on an "AS IS" BASIS,
    12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13   * See the License for the specific language governing permissions and
    14   * limitations under the License.
    15   */
    16  /* Generated By:JavaCC: Do not edit this line. ParseException.java Version 2.1 */
    17  package org.apache.commons.jexl.parser;
    18
    19  /***
    20   * This exception is thrown when parse errors are encountered. You can
    21   * explicitly create objects of this exception type by calling the method
    22   * generateParseException in the generated parser.
    23   *
    24   * You can modify this class to customize your error reporting mechanisms so
    25   * long as you retain the public fields.
    26   */
    27  public class ParseException extends Exception {
    28
    29      /*** serialization version id jdk13 generated. */
    30      static final long serialVersionUID = 654626477565941968L;
    31
    32      /***
    33       * This constructor is used by the method "generateParseException" in the
    34       * generated parser. Calling this constructor generates a new object of this
    35       * type with the fields "currentToken", "expectedTokenSequences", and
    36       * "tokenImage" set. The boolean flag "specialConstructor" is also set to
    37       * true to indicate that this constructor was used to create this object.
    38       * This constructor calls its super class with the empty string to force the
    39       * "toString" method of parent class "Throwable" to print the error message
    40       * in the form: ParseException: (result of getMessage)
    41       */
    42      public ParseException(Token currentTokenVal, int[][] expectedTokenSequencesVal, String[] tokenImageVal) {
    43          super("");
    44          specialConstructor = true;
    45          currentToken = currentTokenVal;
    46          expectedTokenSequences = expectedTokenSequencesVal;
    47          tokenImage = tokenImageVal;
    48      }
    49
    50      /***
    51       * The following constructors are for use by you for whatever purpose you
    52       * can think of. Constructing the exception in this manner makes the
    53       * exception behave in the normal way - i.e., as documented in the class
    54       * "Throwable". The fields "errorToken", "expectedTokenSequences", and
    55       * "tokenImage" do not contain relevant information. The JavaCC generated
    56       * code does not use these constructors.
    57       */
    58
    59      public ParseException() {
    60          super();
    61          specialConstructor = false;
    62      }
    63
    64      public ParseException(String message) {
    65          super(message);
    66          specialConstructor = false;
    67      }
    68
    69      /***
    70       * This variable determines which constructor was used to create this object
    71       * and thereby affects the semantics of the "getMessage" method (see below).
    72       */
    73      protected boolean specialConstructor;
    74
    75      /***
    76       * This is the last token that has been consumed successfully. If this
    77       * object has been created due to a parse error, the token followng this
    78       * token will (therefore) be the first error token.
    79       */
    80      public Token currentToken;
    81
    82      /***
    83       * Each entry in this array is an array of integers. Each array of integers
    84       * represents a sequence of tokens (by their ordinal values) that is
    85       * expected at this point of the parse.
    86       */
    87      public int[][] expectedTokenSequences;
    88
    89      /***
    90       * This is a reference to the "tokenImage" array of the generated parser
    91       * within which the parse error occurred. This array is defined in the
    92       * generated ...Constants interface.
    93       */
    94      public String[] tokenImage;
    95
    96      /***
    97       * This method has the standard behavior when this object has been created
    98       * using the standard constructors. Otherwise, it uses "currentToken" and
    99       * "expectedTokenSequences" to generate a parse error message and returns
    100      * it. If this object has been created due to a parse error, and you do not
    101      * catch it (it gets thrown from the parser), then this method is called
    102      * during the printing of the final stack trace, and hence the correct error
    103      * message gets displayed.
    104      */
    105     public String getMessage() {
    106         if (!specialConstructor) {
    107             return super.getMessage();
    108         }
    109         String expected = "";
    110         int maxSize = 0;
    111         for (int i = 0; i < expectedTokenSequences.length; i++) {
    112             if (maxSize < expectedTokenSequences[i].length) {
    113                 maxSize = expectedTokenSequences[i].length;
    114             }
    115             for (int j = 0; j < expectedTokenSequences[i].length; j++) {
    116                 expected += tokenImage[expectedTokenSequences[i][j]] + " ";
    117             }
    118             if (expectedTokenSequences[i][expectedTokenSequences[i].length - 1] != 0) {
    119                 expected += "...";
    120             }
    121             expected += eol + "    ";
    122         }
    123         String retval = "Encountered \"";
    124         Token tok = currentToken.next;
    125         for (int i = 0; i < maxSize; i++) {
    126             if (i != 0)
    127                 retval += " ";
    128             if (tok.kind == 0) {
    129                 retval += tokenImage[0];
    130                 break;
    131             }
    132             retval += add_escapes(tok.image);
    133             tok = tok.next;
    134         }
    135         retval += "\" at line " + currentToken.next.beginLine + ", column " + currentToken.next.beginColumn;
    136         retval += "." + eol;
    137         if (expectedTokenSequences.length == 1) {
    138             retval += "Was expecting:" + eol + "    ";
    139         } else {
    140             retval += "Was expecting one of:" + eol + "    ";
    141         }
    142         retval += expected;
    143         return retval;
    144     }
    145
    146     /***
    147      * The end of line string for this machine.
    148      */
    149     protected String eol = System.getProperty("line.separator", "\n");
    150
    151     /***
    152      * Used to convert raw characters to their escaped version when these raw
    153      * version cannot be used as part of an ASCII string literal.
    154      */
    155     protected String add_escapes(String str) {
    156         StringBuffer retval = new StringBuffer();
    157         char ch;
    158         for (int i = 0; i < str.length(); i++) {
    159             switch (str.charAt(i)) {
    160                 case 0:
    161                     continue;
    162                 case '\b':
    163                     retval.append("//b");
    164                     continue;
    165                 case '\t':
    166                     retval.append("//t");
    167                     continue;
    168                 case '\n':
    169                     retval.append("//n");
    170                     continue;
    171                 case '\f':
    172                     retval.append("//f");
    173                     continue;
    174                 case '\r':
    175                     retval.append("//r");
    176                     continue;
    177                 case '\"':
    178                     retval.append("//\"");
    179                     continue;
    180                 case '\'':
    181                     retval.append("//\'");
    182                     continue;
    183                 case '//':
    184                     retval.append("////");
    185                     continue;
    186                 default:
    187                     if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
    188                         String s = "0000" + Integer.toString(ch, 16);
    189                         retval.append("//u").append(s.substring(s.length() - 4, s.length()));
    190                     } else {
    191                         retval.append(ch);
    192                     }
    193                     continue;
    194             }
    195         }
    196         return retval.toString();
    197     }
    198
    199 }