001: /* Generated By:JavaCC: Do not edit this line. ParseException.java Version 0.7pre6 */
002: package org.python.parser;
003:
004: /**
005: * This exception is thrown when parse errors are encountered.
006: * You can explicitly create objects of this exception type by
007: * calling the method generateParseException in the generated
008: * parser.
009: *
010: * You can modify this class to customize your error reporting
011: * mechanisms so long as you retain the public fields.
012: */
013: public class ParseException extends Exception {
014:
015: /**
016: * This constructor is used by the method "generateParseException"
017: * in the generated parser. Calling this constructor generates
018: * a new object of this type with the fields "currentToken",
019: * "expectedTokenSequences", and "tokenImage" set. The boolean
020: * flag "specialConstructor" is also set to true to indicate that
021: * this constructor was used to create this object.
022: * This constructor calls its super class with the empty string
023: * to force the "toString" method of parent class "Throwable" to
024: * print the error message in the form:
025: * ParseException: <result of getMessage>
026: */
027: public ParseException(Token currentTokenVal,
028: int[][] expectedTokenSequencesVal, String[] tokenImageVal) {
029: super ("");
030: specialConstructor = true;
031: currentToken = currentTokenVal;
032: expectedTokenSequences = expectedTokenSequencesVal;
033: tokenImage = tokenImageVal;
034: }
035:
036: /**
037: * The following constructors are for use by you for whatever
038: * purpose you can think of. Constructing the exception in this
039: * manner makes the exception behave in the normal way - i.e., as
040: * documented in the class "Throwable". The fields "errorToken",
041: * "expectedTokenSequences", and "tokenImage" do not contain
042: * relevant information. The JavaCC generated code does not use
043: * these constructors.
044: */
045:
046: public ParseException() {
047: super ();
048: specialConstructor = false;
049: }
050:
051: public ParseException(String message) {
052: super (message);
053: specialConstructor = false;
054: }
055:
056: public ParseException(String message, SimpleNode node) {
057: super (message);
058: // If a node is passed in, provide just enough info to get current line/column out
059: Token t = new Token();
060: t.beginLine = node.beginLine;
061: t.beginColumn = node.beginColumn;
062:
063: currentToken = new Token();
064: currentToken.next = t;
065: t = currentToken;
066: t.beginLine = node.beginLine;
067: t.beginColumn = node.beginColumn;
068:
069: specialConstructor = false;
070: }
071:
072: /**
073: * This variable determines which constructor was used to create
074: * this object and thereby affects the semantics of the
075: * "getMessage" method (see below).
076: */
077: protected boolean specialConstructor;
078:
079: /**
080: * This is the last token that has been consumed successfully. If
081: * this object has been created due to a parse error, the token
082: * followng this token will (therefore) be the first error token.
083: */
084: public Token currentToken;
085:
086: /**
087: * Each entry in this array is an array of integers. Each array
088: * of integers represents a sequence of tokens (by their ordinal
089: * values) that is expected at this point of the parse.
090: */
091: public int[][] expectedTokenSequences;
092:
093: /**
094: * This is a reference to the "tokenImage" array of the generated
095: * parser within which the parse error occurred. This array is
096: * defined in the generated ...Constants interface.
097: */
098: public String[] tokenImage;
099:
100: /**
101: * This method has the standard behavior when this object has been
102: * created using the standard constructors. Otherwise, it uses
103: * "currentToken" and "expectedTokenSequences" to generate a parse
104: * error message and returns it. If this object has been created
105: * due to a parse error, and you do not catch it (it gets thrown
106: * from the parser), then this method is called during the printing
107: * of the final stack trace, and hence the correct error message
108: * gets displayed.
109: */
110: public static boolean verboseExceptions = false;
111:
112: public String getMessage() {
113: if (!specialConstructor) {
114: return super .getMessage();
115: }
116: if (verboseExceptions) {
117: String expected = "";
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 += tokenImage[expectedTokenSequences[i][j]]
125: + " ";
126: }
127: if (expectedTokenSequences[i][expectedTokenSequences[i].length - 1] != 0) {
128: expected += "...";
129: }
130: expected += eol + " ";
131: }
132: String retval = "Encountered \"";
133: Token tok = currentToken.next;
134: for (int i = 0; i < maxSize; i++) {
135: if (i != 0)
136: retval += " ";
137: if (tok.kind == 0) {
138: retval += tokenImage[0];
139: break;
140: }
141: retval += add_escapes(tok.image);
142: tok = tok.next;
143: }
144: retval += "\" at line " + currentToken.next.beginLine
145: + ", column " + currentToken.next.beginColumn + "."
146: + eol;
147: if (expectedTokenSequences.length == 1) {
148: retval += "Was expecting:" + eol + " ";
149: } else {
150: retval += "Was expecting one of:" + eol + " ";
151: }
152: retval += expected;
153: return retval;
154: } else {
155: return "invalid syntax";
156: }
157: }
158:
159: /**
160: * The end of line string for this machine.
161: */
162: protected String eol = System.getProperty("line.separator", "\n");
163:
164: /**
165: * Used to convert raw characters to their escaped version
166: * when these raw version cannot be used as part of an ASCII
167: * string literal.
168: */
169: protected String add_escapes(String str) {
170: StringBuffer retval = new StringBuffer();
171: char ch;
172: for (int i = 0; i < str.length(); i++) {
173: switch (str.charAt(i)) {
174: case 0:
175: continue;
176: case '\b':
177: retval.append("\\b");
178: continue;
179: case '\t':
180: retval.append("\\t");
181: continue;
182: case '\n':
183: retval.append("\\n");
184: continue;
185: case '\f':
186: retval.append("\\f");
187: continue;
188: case '\r':
189: retval.append("\\r");
190: continue;
191: case '\"':
192: retval.append("\\\"");
193: continue;
194: case '\'':
195: retval.append("\\\'");
196: continue;
197: case '\\':
198: retval.append("\\\\");
199: continue;
200: default:
201: if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
202: String s = "0000" + Integer.toString(ch, 16);
203: retval.append("\\u"
204: + s.substring(s.length() - 4, s.length()));
205: } else {
206: retval.append(ch);
207: }
208: continue;
209: }
210: }
211: return retval.toString();
212: }
213:
214: }
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