presto-iceberg/src/main/java/io/prestosql/plugin/iceberg/util/PageListBuilder.java/PageListBuilder/build
class PageListBuilder:    public List<Page> build()
    {
        checkArgument(channel == -1, "cannot be in row");
        if (!pageBuilder.isEmpty()) {
            pages.add(pageBuilder.build());
            pageBuilder.reset();
        }
        return pages.build();
    }