org.apache.flink.streaming.runtime.io

Class StreamRecordWriter<T extends IOReadableWritable>

java.lang.Object

org.apache.flink.runtime.io.network.api.writer.RecordWriter<T>

org.apache.flink.streaming.runtime.io.StreamRecordWriter<T>

Type Parameters:

T - The type of elements written.

@Internal
public class StreamRecordWriter<T extends IOReadableWritable>
extends RecordWriter<T>

This record writer keeps data in buffers at most for a certain timeout. It spawns a separate thread that flushes the outputs in a defined interval, to make sure data does not linger in the buffers for too long.

Field Summary

Fields inherited from class org.apache.flink.runtime.io.network.api.writer.RecordWriter

targetPartition

Constructor Summary

Constructors

Constructor and Description
StreamRecordWriter(ResultPartitionWriter writer, ChannelSelector<T> channelSelector, long timeout)
StreamRecordWriter(ResultPartitionWriter writer, ChannelSelector<T> channelSelector, long timeout, String taskName)

Method Summary

Modifier and Type	Method and Description
void	broadcastEmit(T record) This is used to broadcast Streaming Watermarks in-band with records.
void	close() Closes the writer.
void	emit(T record)
void	randomEmit(T record) This is used to send LatencyMarks to a random target channel.

Methods inherited from class org.apache.flink.runtime.io.network.api.writer.RecordWriter

broadcastEvent, clearBuffers, flushAll, setMetricGroup

Methods inherited from class java.lang.Object

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

Constructor Detail

StreamRecordWriter

public StreamRecordWriter(ResultPartitionWriter writer,
                          ChannelSelector<T> channelSelector,
                          long timeout)

StreamRecordWriter

public StreamRecordWriter(ResultPartitionWriter writer,
                          ChannelSelector<T> channelSelector,
                          long timeout,
                          String taskName)

Method Detail

emit

public void emit(T record)
          throws IOException,
                 InterruptedException

Overrides:

emit in class RecordWriter<T extends IOReadableWritable>

Throws:

IOException

InterruptedException

broadcastEmit

public void broadcastEmit(T record)
                   throws IOException,
                          InterruptedException

Description copied from class: RecordWriter

This is used to broadcast Streaming Watermarks in-band with records. This ignores the ChannelSelector.

Overrides:

broadcastEmit in class RecordWriter<T extends IOReadableWritable>

Throws:

IOException

InterruptedException

randomEmit

public void randomEmit(T record)
                throws IOException,
                       InterruptedException

Description copied from class: RecordWriter

This is used to send LatencyMarks to a random target channel.

Overrides:

randomEmit in class RecordWriter<T extends IOReadableWritable>

Throws:

IOException

InterruptedException

close

public void close()

Closes the writer. This stops the flushing thread (if there is one).