SortMergedPartitionResultIterator.java 文件源码

@Override
public GTRecord next() {
    if (!hasNext()) {
        throw new NoSuchElementException();
    }
    // get smallest record
    PeekingIterator<GTRecord> it = heap.poll();
    // WATCH OUT! record got from PartitionResultIterator.next() may changed later,
    // so we must make a shallow copy of it.
    record.shallowCopyFrom(it.next());

    if (it.hasNext()) {
        heap.offer(it);
    }

    return record;
}