presto-hive/src/main/java/io/prestosql/plugin/hive/HiveBooleanParser.java/HiveBooleanParser/isTrue
class HiveBooleanParser:    @SuppressWarnings("PointlessArithmeticExpression")
    public static boolean isTrue(byte[] bytes, int start, int length)
    {
        return (length == 4) &&
                (toUpperCase(bytes[start + 0]) == 'T') &&
                (toUpperCase(bytes[start + 1]) == 'R') &&
                (toUpperCase(bytes[start + 2]) == 'U') &&
                (toUpperCase(bytes[start + 3]) == 'E');
    }