1 /* Generated By:JavaCC: Do not edit this line. ParseException.java Version 3.0 */
2 package org.apache.velocity.runtime.parser;
3
4 /**
5 * This exception is thrown when parse errors are encountered.
6 * It is intended to be caught and typically will be rethrown
7 * as a ParseErrorException.
8 *
9 * <p>You can explicitly create objects of this exception type by
10 * calling the method generateParseException in the generated
11 * parser.
12 *
13 * You can modify this class to customize your error reporting
14 * mechanisms so long as you retain the public fields.
15 */
16 public class ParseException extends Exception {
17
18 private static final long serialVersionUID = -309603325673449381L;
19
20 /**
21 * This constructor is used by the method "generateParseException"
22 * in the generated parser. Calling this constructor generates
23 * a new object of this type with the fields "currentToken",
24 * "expectedTokenSequences", and "tokenImage" set. The boolean
25 * flag "specialConstructor" is also set to true to indicate that
26 * this constructor was used to create this object.
27 * This constructor calls its super class with the empty string
28 * to force the "toString" method of parent class "Throwable" to
29 * print the error message in the form:
30 * ParseException: <result of getMessage>
31 */
32 public ParseException(Token currentTokenVal,
33 int[][] expectedTokenSequencesVal,
34 String[] tokenImageVal
35 )
36 {
37 super("");
38 specialConstructor = true;
39 currentToken = currentTokenVal;
40 expectedTokenSequences = expectedTokenSequencesVal;
41 tokenImage = tokenImageVal;
42 }
43
44 /**
45 * The following constructors are for use by you for whatever
46 * purpose you can think of. Constructing the exception in this
47 * manner makes the exception behave in the normal way - i.e., as
48 * documented in the class "Throwable". The fields "errorToken",
49 * "expectedTokenSequences", and "tokenImage" do not contain
50 * relevant information. The JavaCC generated code does not use
51 * these constructors.
52 */
53
54 public ParseException() {
55 super();
56 specialConstructor = false;
57 }
58
59 public ParseException(String message) {
60 super(message);
61 specialConstructor = false;
62 }
63
64 /**
65 * This variable determines which constructor was used to create
66 * this object and thereby affects the semantics of the
67 * "getMessage" method (see below).
68 */
69 protected boolean specialConstructor;
70
71 /**
72 * This is the last token that has been consumed successfully. If
73 * this object has been created due to a parse error, the token
74 * followng this token will (therefore) be the first error token.
75 */
76 public Token currentToken;
77
78 /**
79 * Each entry in this array is an array of integers. Each array
80 * of integers represents a sequence of tokens (by their ordinal
81 * values) that is expected at this point of the parse.
82 */
83 public int[][] expectedTokenSequences;
84
85 /**
86 * This is a reference to the "tokenImage" array of the generated
87 * parser within which the parse error occurred. This array is
88 * defined in the generated ...Constants interface.
89 */
90 public String[] tokenImage;
91
92 /**
93 * This method has the standard behavior when this object has been
94 * created using the standard constructors. Otherwise, it uses
95 * "currentToken" and "expectedTokenSequences" to generate a parse
96 * error message and returns it. If this object has been created
97 * due to a parse error, and you do not catch it (it gets thrown
98 * from the parser), then this method is called during the printing
99 * of the final stack trace, and hence the correct error message
100 * gets displayed.
101 */
102 public String getMessage() {
103 if (!specialConstructor) {
104 return super.getMessage();
105 }
106 String expected = "";
107 int maxSize = 0;
108 for (int i = 0; i < expectedTokenSequences.length; i++) {
109 if (maxSize < expectedTokenSequences[i].length) {
110 maxSize = expectedTokenSequences[i].length;
111 }
112 for (int j = 0; j < expectedTokenSequences[i].length; j++) {
113 expected += tokenImage[expectedTokenSequences[i][j]] + " ";
114 }
115 if (expectedTokenSequences[i][expectedTokenSequences[i].length - 1] != 0) {
116 expected += "...";
117 }
118 expected += eol + " ";
119 }
120 String retval = "Encountered \"";
121 Token tok = currentToken.next;
122 for (int i = 0; i < maxSize; i++) {
123 if (i != 0) retval += " ";
124 if (tok.kind == 0) {
125 retval += tokenImage[0];
126 break;
127 }
128 retval += add_escapes(tok.image);
129 tok = tok.next;
130 }
131 retval += "\" at line " + currentToken.next.beginLine + ", column " + currentToken.next.beginColumn;
132 retval += "." + eol;
133 if (expectedTokenSequences.length == 1) {
134 retval += "Was expecting:" + eol + " ";
135 } else {
136 retval += "Was expecting one of:" + eol + " ";
137 }
138 retval += expected;
139 return retval;
140 }
141
142 /**
143 * The end of line string for this machine.
144 */
145 protected String eol = System.getProperty("line.separator", "\n");
146
147 /**
148 * Used to convert raw characters to their escaped version
149 * when these raw version cannot be used as part of an ASCII
150 * string literal.
151 */
152 protected String add_escapes(String str) {
153 StringBuffer retval = new StringBuffer();
154 char ch;
155 for (int i = 0; i < str.length(); i++) {
156 switch (str.charAt(i))
157 {
158 case 0 :
159 continue;
160 case '\b':
161 retval.append("\\b");
162 continue;
163 case '\t':
164 retval.append("\\t");
165 continue;
166 case '\n':
167 retval.append("\\n");
168 continue;
169 case '\f':
170 retval.append("\\f");
171 continue;
172 case '\r':
173 retval.append("\\r");
174 continue;
175 case '\"':
176 retval.append("\\\"");
177 continue;
178 case '\'':
179 retval.append("\\\'");
180 continue;
181 case '\\':
182 retval.append("\\\\");
183 continue;
184 default:
185 if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
186 String s = "0000" + Integer.toString(ch, 16);
187 retval.append("\\u" + s.substring(s.length() - 4, s.length()));
188 } else {
189 retval.append(ch);
190 }
191 continue;
192 }
193 }
194 return retval.toString();
195 }
196
197 }