javacc-7.0.3.bin.templates.gwt.ParseException.template Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of javacc Show documentation
Show all versions of javacc Show documentation
JavaCC is a parser/scanner generator for java.
/**
* This exception is thrown when parse errors are encountered.
* You can explicitly create objects of this exception type by
* calling the method generateParseException in the generated
* parser.
*
* You can modify this class to customize your error reporting
* mechanisms so long as you retain the public fields.
*/
public class ParseException extends Exception {
/**
* The version identifier for this Serializable class.
* Increment only if the serialized form of the
* class changes.
*/
private static final long serialVersionUID = 1L;
private static final String INDENT = " ";
/**
* The end of line string (we do not use System.getProperty("") so that we are compatible with Android/GWT);
*/
protected static String EOL = "\n";
public ParseException(Token currentTokenVal,
int[][] expectedTokenSequencesVal,
String[] tokenImageVal
)
{
this (currentTokenVal, expectedTokenSequencesVal, tokenImageVal, null);
}
/**
* This constructor is used by the method "generateParseException"
* in the generated parser. Calling this constructor generates
* a new object of this type with the fields "currentToken",
* "expectedTokenSequences", and "tokenImage" set.
*/
public ParseException(Token currentTokenVal,
int[][] expectedTokenSequencesVal,
String[] tokenImageVal,
String lexicalStateName
)
{
super(initialise(currentTokenVal, expectedTokenSequencesVal, tokenImageVal, lexicalStateName));
currentToken = currentTokenVal;
expectedTokenSequences = expectedTokenSequencesVal;
tokenImage = tokenImageVal;
}
/**
* The following constructors are for use by you for whatever
* purpose you can think of. Constructing the exception in this
* manner makes the exception behave in the normal way - i.e., as
* documented in the class "Throwable". The fields "errorToken",
* "expectedTokenSequences", and "tokenImage" do not contain
* relevant information. The JavaCC generated code does not use
* these constructors.
*/
public ParseException() {
super();
}
/** Constructor with message. */
public ParseException(String message) {
super(message);
}
/**
* This is the last token that has been consumed successfully. If
* this object has been created due to a parse error, the token
* followng this token will (therefore) be the first error token.
*/
public Token currentToken;
/**
* Each entry in this array is an array of integers. Each array
* of integers represents a sequence of tokens (by their ordinal
* values) that is expected at this point of the parse.
*/
public int[][] expectedTokenSequences;
/**
* This is a reference to the "tokenImage" array of the generated
* parser within which the parse error occurred. This array is
* defined in the generated ...Constants interface.
*/
public String[] tokenImage;
/**
* It uses "currentToken" and "expectedTokenSequences" to generate a parse
* error message and returns it. If this object has been created
* due to a parse error, and you do not catch it (it gets thrown
* from the parser) the correct error message
* gets displayed.
*/
private static String initialise(Token currentToken,
int[][] expectedTokenSequences,
String[] tokenImage,
String lexicalStateName) {
StringBuilder sb = new StringBuilder();
StringBuffer expected = new StringBuffer();
int maxSize = 0;
java.util.TreeSet sortedOptions = new java.util.TreeSet();
for (int i = 0; i < expectedTokenSequences.length; i++) {
if (maxSize < expectedTokenSequences[i].length) {
maxSize = expectedTokenSequences[i].length;
}
for (int j = 0; j < expectedTokenSequences[i].length; j++) {
sortedOptions.add(tokenImage[expectedTokenSequences[i][j]]);
}
}
for (String option : sortedOptions) {
expected.append(INDENT).append(option).append(EOL);
}
sb.append("Encountered unexpected token:");
Token tok = currentToken.next;
for (int i = 0; i < maxSize; i++) {
String tokenText = tok.image;
String escapedTokenText = add_escapes(tokenText);
if (i != 0) {
sb.append(" ");
}
if (tok.kind == 0) {
sb.append(tokenImage[0]);
break;
}
sb.append(" \"");
sb.append(escapedTokenText);
sb.append("\"");
sb.append(" " + tokenImage[tok.kind]);
tok = tok.next;
}
#if KEEP_LINE_COLUMN
sb.append(EOL).append(INDENT).append("at line " + currentToken.next.beginLine + ", column " + currentToken.next.beginColumn);
#fi
sb.append(".").append(EOL);
if (expectedTokenSequences.length == 0) {
// Nothing to add here
} else {
int numExpectedTokens = expectedTokenSequences.length;
sb.append(EOL).append("Was expecting"+ (numExpectedTokens == 1 ? ":" : " one of:") + EOL + EOL);
sb.append(expected.toString());
}
// 2013/07/30 --> Seems to be inaccurate as represents the readahead state, not the lexical state BEFORE the unknown token
// if (lexicalStateName != null) {
// sb.append(EOL).append("** Lexical State : ").append(lexicalStateName).append(EOL).append(EOL);
// }
return sb.toString();
}
/**
* Used to convert raw characters to their escaped version
* when these raw version cannot be used as part of an ASCII
* string literal.
*/
static String add_escapes(String str) {
StringBuffer retval = new StringBuffer();
char ch;
for (int i = 0; i < str.length(); i++) {
switch (str.charAt(i))
{
case '\b':
retval.append("\\b");
continue;
case '\t':
retval.append("\\t");
continue;
case '\n':
retval.append("\\n");
continue;
case '\f':
retval.append("\\f");
continue;
case '\r':
retval.append("\\r");
continue;
case '\"':
retval.append("\\\"");
continue;
case '\'':
retval.append("\\\'");
continue;
case '\\':
retval.append("\\\\");
continue;
default:
if ((ch = str.charAt(i)) < 0x20 || ch > 0x7e) {
String s = "0000" + Integer.toString(ch, 16);
retval.append("\\u" + s.substring(s.length() - 4, s.length()));
} else {
retval.append(ch);
}
continue;
}
}
return retval.toString();
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy