presto-spi/src/main/java/io/prestosql/spi/block/SingleRowBlockWriter.java/SingleRowBlockWriter/SingleRowBlockWriter
class SingleRowBlockWriter:    SingleRowBlockWriter(int rowIndex, BlockBuilder[] fieldBlockBuilders)
    {
        super(rowIndex);
        this.fieldBlockBuilders = fieldBlockBuilders;
        long initialBlockBuilderSize = 0;
        for (BlockBuilder fieldBlockBuilder : fieldBlockBuilders) {
            initialBlockBuilderSize += fieldBlockBuilder.getSizeInBytes();
        }
        this.initialBlockBuilderSize = initialBlockBuilderSize;
    }