org.apache.flink.runtime.io.network.api.writer

Class RecordWriter<T extends IOReadableWritable>

java.lang.Object

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

Type Parameters:

T - the type of the record that can be emitted with this record writer

Direct Known Subclasses:

BroadcastRecordWriter

public class RecordWriter<T extends IOReadableWritable>
extends Object

A record-oriented runtime result writer.

The RecordWriter wraps the runtime's ResultPartitionWriter and takes care of serializing records into buffers.

Important: it is necessary to call flushAll() after all records have been written with emit(IOReadableWritable). This ensures that all produced records are written to the output stream (incl. partially filled ones).

Constructor Summary

Constructors

Constructor and Description
RecordWriter(ResultPartitionWriter writer)
RecordWriter(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	broadcastEvent(AbstractEvent event)
void	clearBuffers()
void	close() Closes the writer.
static RecordWriter	createRecordWriter(ResultPartitionWriter writer, ChannelSelector channelSelector, long timeout, String taskName)
static RecordWriter	createRecordWriter(ResultPartitionWriter writer, ChannelSelector channelSelector, String taskName)
void	emit(T record)
void	flushAll()
void	randomEmit(T record) This is used to send LatencyMarks to a random target channel.
void	setMetricGroup(TaskIOMetricGroup metrics) Sets the metric group for this RecordWriter.

Methods inherited from class java.lang.Object

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

Constructor Detail

RecordWriter

public RecordWriter(ResultPartitionWriter writer)

RecordWriter

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

Method Detail

emit

public void emit(T record)
          throws IOException,
                 InterruptedException

Throws:

IOException

InterruptedException

broadcastEmit

public void broadcastEmit(T record)
                   throws IOException,
                          InterruptedException

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

Throws:

IOException

InterruptedException

randomEmit

public void randomEmit(T record)
                throws IOException,
                       InterruptedException

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

Throws:

IOException

InterruptedException

broadcastEvent

public void broadcastEvent(AbstractEvent event)
                    throws IOException

Throws:

IOException

flushAll

public void flushAll()

clearBuffers

public void clearBuffers()

setMetricGroup

public void setMetricGroup(TaskIOMetricGroup metrics)

Sets the metric group for this RecordWriter.

close

public void close()

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

createRecordWriter

public static RecordWriter createRecordWriter(ResultPartitionWriter writer,
                                              ChannelSelector channelSelector,
                                              long timeout,
                                              String taskName)

createRecordWriter

public static RecordWriter createRecordWriter(ResultPartitionWriter writer,
                                              ChannelSelector channelSelector,
                                              String taskName)