1 /* Generated By:JavaCC: Do not edit this line. ParseException.java Version 2.1 */
2 package org.apache.commons.el.parser;
3
4 /**
5 * This exception is thrown when parse errors are encountered.
6 * You can explicitly create objects of this exception type by
7 * calling the method generateParseException in the generated
8 * parser.
9 *
10 * You can modify this class to customize your error reporting
11 * mechanisms so long as you retain the public fields.
12 */
13 public class ParseException extends Exception {
14
15 /**
16 * This constructor is used by the method "generateParseException"
17 * in the generated parser. Calling this constructor generates
18 * a new object of this type with the fields "currentToken",
19 * "expectedTokenSequences", and "tokenImage" set. The boolean
20 * flag "specialConstructor" is also set to true to indicate that
21 * this constructor was used to create this object.
22 * This constructor calls its super class with the empty string
23 * to force the "toString" method of parent class "Throwable" to
24 * print the error message in the form:
25 * ParseException: <result of getMessage>
26 */
27 public ParseException(Token currentTokenVal,
28 int[][] expectedTokenSequencesVal,
29 String[] tokenImageVal
30 )
31 {
32 super("");
33 specialConstructor = true;
34 currentToken = currentTokenVal;
35 expectedTokenSequences = expectedTokenSequencesVal;
36 tokenImage = tokenImageVal;
37 }
38
39 /**
40 * The following constructors are for use by you for whatever
41 * purpose you can think of. Constructing the exception in this
42 * manner makes the exception behave in the normal way - i.e., as
43 * documented in the class "Throwable". The fields "errorToken",
44 * "expectedTokenSequences", and "tokenImage" do not contain
45 * relevant information. The JavaCC generated code does not use
46 * these constructors.
47 */
48
49 public ParseException() {
50 super();
51 specialConstructor = false;
52 }
53
54 public ParseException(String message) {
55 super(message);
56 specialConstructor = false;
57 }
58
59 /**
60 * This variable determines which constructor was used to create
61 * this object and thereby affects the semantics of the
62 * "getMessage" method (see below).
63 */
64 protected boolean specialConstructor;
65
66 /**
67 * This is the last token that has been consumed successfully. If
68 * this object has been created due to a parse error, the token
69 * followng this token will (therefore) be the first error token.
70 */
71 public Token currentToken;
72
73 /**
74 * Each entry in this array is an array of integers. Each array
75 * of integers represents a sequence of tokens (by their ordinal
76 * values) that is expected at this point of the parse.
77 */
78 public int[][] expectedTokenSequences;
79
80 /**
81 * This is a reference to the "tokenImage" array of the generated
82 * parser within which the parse error occurred. This array is
83 * defined in the generated ...Constants interface.
84 */
85 public String[] tokenImage;
86
87 /**
88 * This method has the standard behavior when this object has been
89 * created using the standard constructors. Otherwise, it uses
90 * "currentToken" and "expectedTokenSequences" to generate a parse
91 * error message and returns it. If this object has been created
92 * due to a parse error, and you do not catch it (it gets thrown
93 * from the parser), then this method is called during the printing
94 * of the final stack trace, and hence the correct error message
95 * gets displayed.
96 */
97 public String getMessage() {
98 if (!specialConstructor) {
99 return super.getMessage();
100 }
101 String expected = "";
102 int maxSize = 0;
103 for (int i = 0; i < expectedTokenSequences.length; i++) {
104 if (maxSize < expectedTokenSequences[i].length) {
105 maxSize = expectedTokenSequences[i].length;
106 }
107 for (int j = 0; j < expectedTokenSequences[i].length; j++) {
108 expected += tokenImage[expectedTokenSequences[i][j]] + " ";
109 }
110 if (expectedTokenSequences[i][expectedTokenSequences[i].length - 1] != 0) {
111 expected += "...";
112 }
113 expected += eol + " ";
114 }
115 String retval = "Encountered \"";
116 Token tok = currentToken.next;
117 for (int i = 0; i < maxSize; i++) {
118 if (i != 0) retval += " ";
119 if (tok.kind == 0) {
120 retval += tokenImage[0];
121 break;
122 }
123 retval += add_escapes(tok.image);
124 tok = tok.next;
125 }
126 retval += "\" at line " + currentToken.next.beginLine + ", column " + currentToken.next.beginColumn;
127 retval += "." + eol;
128 if (expectedTokenSequences.length == 1) {
129 retval += "Was expecting:" + eol + " ";
130 } else {
131 retval += "Was expecting one of:" + eol + " ";
132 }
133 retval += expected;
134 return retval;
135 }
136
137 /**
138 * The end of line string for this machine.
139 */
140 protected String eol = System.getProperty("line.separator", "\n");
141
142 /**
143 * Used to convert raw characters to their escaped version
144 * when these raw version cannot be used as part of an ASCII
145 * string literal.
146 */
147 protected String add_escapes(String str) {
148 StringBuffer retval = new StringBuffer();
149 char ch;
150 for (int i = 0, length = str.length(); i < length; i++) {
151 switch (str.charAt(i))
152 {
153 case 0 :
154 continue;
155 case '\b':
156 retval.append("\\b");
157 continue;
158 case '\t':
159 retval.append("\\t");
160 continue;
161 case '\n':
162 retval.append("\\n");
163 continue;
164 case '\f':
165 retval.append("\\f");
166 continue;
167 case '\r':
168 retval.append("\\r");
169 continue;
170 case '\"':
171 retval.append("\\\"");
172 continue;
173 case '\'':
174 retval.append("\\\'");
175 continue;
176 case '\\':
177 retval.append("\\\\");
178 continue;
179 default:
180 if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
181 String s = "0000" + Integer.toString(ch, 16);
182 retval.append("\\u" + s.substring(s.length() - 4, s.length()));
183 } else {
184 retval.append(ch);
185 }
186 continue;
187 }
188 }
189 return retval.toString();
190 }
191
192 }