org.apache.seatunnel.api.source

接口 SourceReader<T,SplitT extends SourceSplit>

类型参数:

T - record type.

SplitT - source split type.

所有超级接口:

AutoCloseable, CheckpointListener

public interface SourceReader<T,SplitT extends SourceSplit>
extends AutoCloseable, CheckpointListener

The SourceReader is used to generate source record, and it will be running at worker.

嵌套类概要

嵌套类

限定符和类型	接口和说明
static interface	SourceReader.Context

方法概要

限定符和类型	方法和说明
void	addSplits(List<SplitT> splits) Add the split checkpoint state to reader.
void	close() Called to close the reader, in case it holds on to any resources, like threads or network connections.
void	handleNoMoreSplits() This method is called when the reader is notified that it will not receive any further splits.
default void	handleSourceEvent(SourceEvent sourceEvent) Handle the source event form SourceSplitEnumerator.
void	open() Open the source reader.
void	pollNext(Collector<T> output) Generate the next batch of records.
List<SplitT>	snapshotState(long checkpointId) Get the current split checkpoint state by checkpointId.

从接口继承的方法 org.apache.seatunnel.api.state.CheckpointListener

notifyCheckpointAborted, notifyCheckpointComplete

方法详细资料

open

void open()
   throws Exception

Open the source reader.

抛出:

Exception

close

void close()
    throws IOException

Called to close the reader, in case it holds on to any resources, like threads or network connections.

指定者:

close 在接口中 AutoCloseable

抛出:

IOException

pollNext

void pollNext(Collector<T> output)
       throws Exception

Generate the next batch of records.

参数:

output - output collector.

抛出:

Exception - if error occurs.

snapshotState

List<SplitT> snapshotState(long checkpointId)
                    throws Exception

Get the current split checkpoint state by checkpointId.

If the source is bounded, checkpoint is not triggered.

参数:

checkpointId - checkpoint Id.

返回:

split checkpoint state.

抛出:

Exception - if error occurs.

addSplits

void addSplits(List<SplitT> splits)

Add the split checkpoint state to reader.

参数:

splits - split checkpoint state.

handleNoMoreSplits

void handleNoMoreSplits()

This method is called when the reader is notified that it will not receive any further splits.

It is triggered when the enumerator calls SourceSplitEnumerator.Context.signalNoMoreSplits(int) with the reader's parallel subtask.

handleSourceEvent

default void handleSourceEvent(SourceEvent sourceEvent)

Handle the source event form SourceSplitEnumerator.

参数:

sourceEvent - source event.