presto-accumulo/src/main/java/io/prestosql/plugin/accumulo/io/AccumuloRecordCursor.java/AccumuloRecordCursor/advanceNextPosition
class AccumuloRecordCursor:    @Override
    public boolean advanceNextPosition()
    {
        try {
            if (iterator.hasNext()) {
                serializer.reset();
                Entry<Key, Value> row = iterator.next();
                for (Entry<Key, Value> entry : WholeRowIterator.decodeRow(row.getKey(), row.getValue()).entrySet()) {
                    bytesRead += entry.getKey().getSize() + entry.getValue().getSize();
                    serializer.deserialize(entry);
                }
                return true;
            }
            else {
                return false;
            }
        }
        catch (IOException e) {
            throw new PrestoException(IO_ERROR, "Caught IO error from serializer on read", e);
        }
    }