E- The type of the record returned by the iterator.
@PublicEvolving public final class SingletonResultIterator<E> extends RecyclableIterator<E> implements BulkFormat.RecordIterator<E>
BulkFormat.RecordIteratorthat returns a single value. The iterator is mutable to support object reuse and supports recycling.
|Constructor and Description|
|Modifier and Type||Method and Description|
Gets the next record from the file, together with its position.
Sets the single record to be returned by this iterator.
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
public void set(E element, long offset, long skipCount)
RecordAndPosition, meaning they need to point to AFTER this specific record (because a checkpoint taken after the record was processed needs to resume from after this record).
@Nullable public RecordAndPosition<E> next()
The position information returned with the record point to the record AFTER the returned record, because it defines the point where the reading should resume once the current record is emitted. The position information is put in the source's state when the record is emitted. If a checkpoint is taken directly after the record is emitted, the checkpoint must to describe where to resume the source reading from after that record.
Objects returned by this method may be reused by the iterator. By the time that this
method is called again, no object returned from the previous call will be referenced any
more. That makes it possible to have a single
MutableRecordAndPosition object and
return the same instance (with updated record and position) on every call.
Copyright © 2014–2021 The Apache Software Foundation. All rights reserved.