@Override
public StructuredDate evaluate(String displayDate) throws StructuredDateFormatException {
stack = new Stack<Object>();
result = new StructuredDate();
result.setDisplayDate(displayDate);
// Instantiate a parser from the lowercased display date, so that parsing will be
// case insensitive.
ANTLRInputStream inputStream = new ANTLRInputStream(displayDate.toLowerCase());
StructuredDateLexer lexer = new StructuredDateLexer(inputStream);
CommonTokenStream tokenStream = new CommonTokenStream(lexer);
StructuredDateParser parser = new StructuredDateParser(tokenStream);
// Don't try to recover from parse errors, just bail.
parser.setErrorHandler(new BailErrorStrategy());
// Don't print error messages to the console.
parser.removeErrorListeners();
// Generate our own custom error messages.
parser.addParseListener(this);
try {
// Attempt to fulfill the oneDisplayDate rule of the grammar.
parser.oneDisplayDate();
} catch (ParseCancellationException e) {
// ParseCancellationException is thrown by the BailErrorStrategy when there is a
// parse error, with the underlying RecognitionException as the cause.
RecognitionException re = (RecognitionException) e.getCause();
throw new StructuredDateFormatException(getErrorMessage(re), re);
}
// The parsing was successful. Return the result.
return result;
}
