default Reader asCharacterStream() {
        // Reader.nullReader() requires JDK 11+
        return new StringReader(isNullOrEmpty() ? "" : asString());
    }
Gets value as character stream. It's caller's responsibility to close the
tream at the end of reading.

@return non-null character stream for reading
clickhouse-data/src/main/java/com/clickhouse/data/ClickHouseValue.java