Examples with CaseInsensitiveStream com.facebook.presto.sql.parser.CaseInsensitiveStream used on opensource projects

Example 1 with CaseInsensitiveStream

use of com.facebook.presto.sql.parser.CaseInsensitiveStream in project presto by prestodb.

the class TypeCalculation method parseTypeCalculation.

private static ParserRuleContext parseTypeCalculation(String calculation) {
    TypeCalculationLexer lexer = new TypeCalculationLexer(new CaseInsensitiveStream(new ANTLRInputStream(calculation)));
    CommonTokenStream tokenStream = new CommonTokenStream(lexer);
    TypeCalculationParser parser = new TypeCalculationParser(tokenStream);
    lexer.removeErrorListeners();
    lexer.addErrorListener(ERROR_LISTENER);
    parser.removeErrorListeners();
    parser.addErrorListener(ERROR_LISTENER);
    ParserRuleContext tree;
    try {
        // first, try parsing with potentially faster SLL mode
        parser.getInterpreter().setPredictionMode(PredictionMode.SLL);
        tree = parser.typeCalculation();
    } catch (ParseCancellationException ex) {
        // if we fail, parse with LL mode
        // rewind input stream
        tokenStream.reset();
        parser.reset();
        parser.getInterpreter().setPredictionMode(PredictionMode.LL);
        tree = parser.typeCalculation();
    }
    return tree;
}