001: /* Generated By:JavaCC: Do not edit this line. ParseException.java Version 3.0 */
002: package japa.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(Token currentTokenVal, String message) {
052: super (message);
053: currentToken = currentTokenVal;
054: specialConstructor = false;
055: }
056:
057: /**
058: * This variable determines which constructor was used to create
059: * this object and thereby affects the semantics of the
060: * "getMessage" method (see below).
061: */
062: protected boolean specialConstructor;
063:
064: /**
065: * This is the last token that has been consumed successfully. If
066: * this object has been created due to a parse error, the token
067: * followng this token will (therefore) be the first error token.
068: */
069: public Token currentToken;
070:
071: /**
072: * Each entry in this array is an array of integers. Each array
073: * of integers represents a sequence of tokens (by their ordinal
074: * values) that is expected at this point of the parse.
075: */
076: public int[][] expectedTokenSequences;
077:
078: /**
079: * This is a reference to the "tokenImage" array of the generated
080: * parser within which the parse error occurred. This array is
081: * defined in the generated ...Constants interface.
082: */
083: public String[] tokenImage;
084:
085: /**
086: * This method has the standard behavior when this object has been
087: * created using the standard constructors. Otherwise, it uses
088: * "currentToken" and "expectedTokenSequences" to generate a parse
089: * error message and returns it. If this object has been created
090: * due to a parse error, and you do not catch it (it gets thrown
091: * from the parser), then this method is called during the printing
092: * of the final stack trace, and hence the correct error message
093: * gets displayed.
094: */
095: @Override
096: public String getMessage() {
097: if (!specialConstructor) {
098: if (currentToken == null) {
099: return super .getMessage();
100: }
101: StringBuilder ret = new StringBuilder();
102: ret.append(super .getMessage());
103: ret.append(": \"");
104: ret.append(currentToken.image);
105: ret.append("\" at line ");
106: ret.append(currentToken.beginLine);
107: ret.append(", column ");
108: ret.append(currentToken.beginColumn);
109: return ret.toString();
110: }
111: StringBuffer expected = new StringBuffer();
112: int maxSize = 0;
113: for (int i = 0; i < expectedTokenSequences.length; i++) {
114: if (maxSize < expectedTokenSequences[i].length) {
115: maxSize = expectedTokenSequences[i].length;
116: }
117: for (int j = 0; j < expectedTokenSequences[i].length; j++) {
118: expected.append(
119: tokenImage[expectedTokenSequences[i][j]])
120: .append(" ");
121: }
122: if (expectedTokenSequences[i][expectedTokenSequences[i].length - 1] != 0) {
123: expected.append("...");
124: }
125: expected.append(eol).append(" ");
126: }
127: String retval = "Encountered \"";
128: Token tok = currentToken.next;
129: for (int i = 0; i < maxSize; i++) {
130: if (i != 0)
131: retval += " ";
132: if (tok.kind == 0) {
133: retval += tokenImage[0];
134: break;
135: }
136: retval += add_escapes(tok.image);
137: tok = tok.next;
138: }
139: retval += "\" at line " + currentToken.next.beginLine
140: + ", column " + currentToken.next.beginColumn;
141: retval += "." + eol;
142: if (expectedTokenSequences.length == 1) {
143: retval += "Was expecting:" + eol + " ";
144: } else {
145: retval += "Was expecting one of:" + eol + " ";
146: }
147: retval += expected.toString();
148: return retval;
149: }
150:
151: /**
152: * The end of line string for this machine.
153: */
154: protected String eol = System.getProperty("line.separator", "\n");
155:
156: /**
157: * Used to convert raw characters to their escaped version
158: * when these raw version cannot be used as part of an ASCII
159: * string literal.
160: */
161: protected String add_escapes(String str) {
162: StringBuffer retval = new StringBuffer();
163: char ch;
164: for (int i = 0; i < str.length(); i++) {
165: switch (str.charAt(i)) {
166: case 0:
167: continue;
168: case '\b':
169: retval.append("\\b");
170: continue;
171: case '\t':
172: retval.append("\\t");
173: continue;
174: case '\n':
175: retval.append("\\n");
176: continue;
177: case '\f':
178: retval.append("\\f");
179: continue;
180: case '\r':
181: retval.append("\\r");
182: continue;
183: case '\"':
184: retval.append("\\\"");
185: continue;
186: case '\'':
187: retval.append("\\\'");
188: continue;
189: case '\\':
190: retval.append("\\\\");
191: continue;
192: default:
193: if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
194: String s = "0000" + Integer.toString(ch, 16);
195: retval.append("\\u"
196: + s.substring(s.length() - 4, s.length()));
197: } else {
198: retval.append(ch);
199: }
200: continue;
201: }
202: }
203: return retval.toString();
204: }
205:
206: }
|