public boolean isEmpty() {
        return length < 1;
    }
Checks whether the buffer is empty or not. Please pay attention that this
will return {@code true} when {@link #length()} is zero, even
{@link #array()} may return an non-empty byte array.

@return true if the buffer is empty; false otherwise
clickhouse-data/src/main/java/com/clickhouse/data/ClickHouseByteBuffer.java