presto-main/src/main/java/io/prestosql/operator/SimplePagesHashStrategy.java/SimplePagesHashStrategy/appendTo
class SimplePagesHashStrategy:    @Override
    public void appendTo(int blockIndex, int position, PageBuilder pageBuilder, int outputChannelOffset)
    {
        for (int outputIndex : outputChannels) {
            Type type = types.get(outputIndex);
            List<Block> channel = channels.get(outputIndex);
            Block block = channel.get(blockIndex);
            type.appendTo(block, position, pageBuilder.getBlockBuilder(outputChannelOffset));
            outputChannelOffset++;
        }
    }