001 /* Generated By:JavaCC: Do not edit this line. ParseException.java Version 3.0 */
002 /**
003 * Licensed to the Apache Software Foundation (ASF) under one or more
004 * contributor license agreements. See the NOTICE file distributed with
005 * this work for additional information regarding copyright ownership.
006 * The ASF licenses this file to You under the Apache License, Version 2.0
007 * (the "License"); you may not use this file except in compliance with
008 * the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018 package org.fusesource.hawtbuf.proto.compiler.parser;
019
020 /**
021 * This exception is thrown when parse errors are encountered.
022 * You can explicitly create objects of this exception type by
023 * calling the method generateParseException in the generated
024 * parser.
025 *
026 * You can modify this class to customize your error reporting
027 * mechanisms so long as you retain the public fields.
028 */
029 public class ParseException extends Exception {
030
031 /**
032 * This constructor is used by the method "generateParseException"
033 * in the generated parser. Calling this constructor generates
034 * a new object of this type with the fields "currentToken",
035 * "expectedTokenSequences", and "tokenImage" set. The boolean
036 * flag "specialConstructor" is also set to true to indicate that
037 * this constructor was used to create this object.
038 * This constructor calls its super class with the empty string
039 * to force the "toString" method of parent class "Throwable" to
040 * print the error message in the form:
041 * ParseException: <result of getMessage>
042 */
043 public ParseException(Token currentTokenVal,
044 int[][] expectedTokenSequencesVal,
045 String[] tokenImageVal
046 )
047 {
048 super("");
049 specialConstructor = true;
050 currentToken = currentTokenVal;
051 expectedTokenSequences = expectedTokenSequencesVal;
052 tokenImage = tokenImageVal;
053 }
054
055 /**
056 * The following constructors are for use by you for whatever
057 * purpose you can think of. Constructing the exception in this
058 * manner makes the exception behave in the normal way - i.e., as
059 * documented in the class "Throwable". The fields "errorToken",
060 * "expectedTokenSequences", and "tokenImage" do not contain
061 * relevant information. The JavaCC generated code does not use
062 * these constructors.
063 */
064
065 public ParseException() {
066 super();
067 specialConstructor = false;
068 }
069
070 public ParseException(String message) {
071 super(message);
072 specialConstructor = false;
073 }
074
075 /**
076 * This variable determines which constructor was used to create
077 * this object and thereby affects the semantics of the
078 * "getMessage" method (see below).
079 */
080 protected boolean specialConstructor;
081
082 /**
083 * This is the last token that has been consumed successfully. If
084 * this object has been created due to a parse error, the token
085 * followng this token will (therefore) be the first error token.
086 */
087 public Token currentToken;
088
089 /**
090 * Each entry in this array is an array of integers. Each array
091 * of integers represents a sequence of tokens (by their ordinal
092 * values) that is expected at this point of the parse.
093 */
094 public int[][] expectedTokenSequences;
095
096 /**
097 * This is a reference to the "tokenImage" array of the generated
098 * parser within which the parse error occurred. This array is
099 * 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 }