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:

StreamRecordWriter

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 flush() 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).

Field Summary

Fields

Modifier and Type	Field and Description
protected ResultPartitionWriter	writer

Constructor Summary

Constructors

Constructor and Description
RecordWriter(ResultPartitionWriter writer)
RecordWriter(ResultPartitionWriter writer, ChannelSelector<T> channelSelector)

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	emit(T record)
void	flush()
void	sendEndOfSuperstep()
void	setReporter(AccumulatorRegistry.Reporter reporter) Counter for the number of records emitted and the records processed.

Methods inherited from class java.lang.Object

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

Field Detail

writer

protected final ResultPartitionWriter writer

Constructor Detail

RecordWriter

public RecordWriter(ResultPartitionWriter writer)

RecordWriter

public RecordWriter(ResultPartitionWriter writer,
                    ChannelSelector<T> channelSelector)

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

broadcastEvent

public void broadcastEvent(AbstractEvent event)
                    throws IOException,
                           InterruptedException

Throws:

IOException

InterruptedException

sendEndOfSuperstep

public void sendEndOfSuperstep()
                        throws IOException,
                               InterruptedException

Throws:

IOException

InterruptedException

flush

public void flush()
           throws IOException

Throws:

IOException

clearBuffers

public void clearBuffers()

setReporter

public void setReporter(AccumulatorRegistry.Reporter reporter)

Counter for the number of records emitted and the records processed.