public String readUnicodeString() throws IOException {
        return readString(readVarInt(), StandardCharsets.UTF_8);
    }
Reads unicode string from input stream.

@return non-null unicode string
@throws IOException when failed to read value from input stream, not able to
                    retrieve all bytes, or reached end of the stream
clickhouse-data/src/main/java/com/clickhouse/data/ClickHouseInputStream.java