Package org.apache.flink.connector.file.src.util

Class IteratorResultIterator<E>

java.lang.Object

org.apache.flink.connector.file.src.util.RecyclableIterator<E>

org.apache.flink.connector.file.src.util.IteratorResultIterator<E>

Type Parameters:

E - The type of the record returned by the iterator.

All Implemented Interfaces:

BulkFormat.RecordIterator<E>

@PublicEvolving
public final class IteratorResultIterator<E>
extends RecyclableIterator<E>
implements BulkFormat.RecordIterator<E>

A simple BulkFormat.RecordIterator that returns the elements of an iterator, augmented with position information.

Constructor Summary

Constructors

Constructor	Description
IteratorResultIterator(Iterator<E> records, long offset, long startingSkipCount)	Creates a new RecordIterator returning the records from the given iterator, augmented with their position information.
IteratorResultIterator(Iterator<E> records, long offset, long startingSkipCount, Runnable recycler)	Creates a new RecordIterator returning the records from the given iterator, augmented with their position information.

Method Summary

Modifier and Type	Method	Description
RecordAndPosition<E>	next()	Gets the next record from the file, together with its position.

Methods inherited from class org.apache.flink.connector.file.src.util.RecyclableIterator

releaseBatch

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.apache.flink.connector.file.src.reader.BulkFormat.RecordIterator

releaseBatch

Constructor Details

IteratorResultIterator

public IteratorResultIterator(Iterator<E> records,
 long offset,
 long startingSkipCount)

Creates a new RecordIterator returning the records from the given iterator, augmented with their position information.

Each record's RecordAndPosition will have the same offset value for RecordAndPosition.getOffset(). The first returned record will have a records-to-skip count of startingSkipCount + 1, following the contract that each record needs to point to the position AFTER itself (because a checkpoint taken after the record was emitted needs to resume from after that record).

IteratorResultIterator

public IteratorResultIterator(Iterator<E> records,
 long offset,
 long startingSkipCount,
 @Nullable
 Runnable recycler)

Creates a new RecordIterator returning the records from the given iterator, augmented with their position information. When the iterator is marked as done (via RecyclableIterator.releaseBatch(), the given recycler is called.

Each record's RecordAndPosition will have the same offset value for RecordAndPosition.getOffset(). The first returned record will have a records-to-skip count of startingSkipCount + 1, following the contract that each record needs to point to the position AFTER itself (because a checkpoint taken after the record was emitted needs to resume from after that record).

Method Details

next

@Nullable
public RecordAndPosition<E> next()

Description copied from interface: BulkFormat.RecordIterator

Gets the next record from the file, together with its position.

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.

Specified by:

next in interface BulkFormat.RecordIterator<E>