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

类 RecordMapperWrapperRecordIterator<I,O>

java.lang.Object

org.apache.flink.connector.file.src.util.RecordMapperWrapperRecordIterator<I,O>

类型参数:

I - Input type

O - Mapped output type

所有已实现的接口:

BulkFormat.RecordIterator<O>

public class RecordMapperWrapperRecordIterator<I,O>
extends Object
implements BulkFormat.RecordIterator<O>

Implementation of BulkFormat.RecordIterator that wraps another iterator and performs the mapping of the records. You can use wrapReader(BulkFormat.Reader, RecordMapper) to wrap a whole reader.

嵌套类概要

嵌套类

限定符和类型	类和说明
static interface	RecordMapperWrapperRecordIterator.RecordMapper<I,O> Record mapper definition.

构造器概要

构造器

构造器和说明
RecordMapperWrapperRecordIterator(BulkFormat.RecordIterator<I> wrapped, RecordMapperWrapperRecordIterator.RecordMapper<I,O> mapper)

方法概要

限定符和类型	方法和说明
RecordAndPosition<O>	next() Gets the next record from the file, together with its position.
void	releaseBatch() Releases the batch that this iterator iterated over.
static <I,O> BulkFormat.Reader<O>	wrapReader(BulkFormat.Reader<I> wrappedReader, RecordMapperWrapperRecordIterator.RecordMapper<I,O> recordMapper) Wrap a BulkFormat.Reader applying a RecordMapperWrapperRecordIterator.RecordMapper on the returned iterator.

从类继承的方法 java.lang.Object

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

构造器详细资料

RecordMapperWrapperRecordIterator

public RecordMapperWrapperRecordIterator(BulkFormat.RecordIterator<I> wrapped,
                                         RecordMapperWrapperRecordIterator.RecordMapper<I,O> mapper)

方法详细资料

next

public RecordAndPosition<O> next()

从接口复制的说明: 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.

指定者:

next 在接口中 BulkFormat.RecordIterator<O>

releaseBatch

public void releaseBatch()

从接口复制的说明: BulkFormat.RecordIterator

Releases the batch that this iterator iterated over. This is not supposed to close the reader and its resources, but is simply a signal that this iterator is no used any more. This method can be used as a hook to recycle/reuse heavyweight object structures.

指定者:

releaseBatch 在接口中 BulkFormat.RecordIterator<O>

wrapReader

public static <I,O> BulkFormat.Reader<O> wrapReader(BulkFormat.Reader<I> wrappedReader,
                                                    RecordMapperWrapperRecordIterator.RecordMapper<I,O> recordMapper)

Wrap a BulkFormat.Reader applying a RecordMapperWrapperRecordIterator.RecordMapper on the returned iterator.

类型参数:

I - Input type

O - Mapped output type