presto-orc/src/main/java/io/prestosql/orc/RowGroup.java/RowGroup/RowGroup
class RowGroup:    public RowGroup(int groupId, long rowOffset, long rowCount, long minAverageRowBytes, InputStreamSources streamSources)
    {
        this.groupId = groupId;
        this.rowOffset = rowOffset;
        this.rowCount = rowCount;
        this.minAverageRowBytes = minAverageRowBytes;
        this.streamSources = requireNonNull(streamSources, "streamSources is null");
    }