org.apache.hadoop.mapred
Class MapTask.MapOutputBuffer<K,V>

java.lang.Object
  org.apache.hadoop.mapred.MapTask.MapOutputBuffer<K,V>

All Implemented Interfaces:

MapOutputCollector<K,V>, org.apache.hadoop.util.IndexedSortable

Enclosing class:

MapTask

@InterfaceAudience.LimitedPrivate(value="MapReduce")
@InterfaceStability.Unstable
public static class MapTask.MapOutputBuffer<K,V>
extends Object
implements MapOutputCollector<K,V>, org.apache.hadoop.util.IndexedSortable

Nested Class Summary

protected class	MapTask.MapOutputBuffer.BlockingBuffer Inner class managing the spill of serialized records to disk.
class	MapTask.MapOutputBuffer.Buffer
protected class	MapTask.MapOutputBuffer.InMemValBytes Inner class wrapping valuebytes, used for appendRaw.
protected class	MapTask.MapOutputBuffer.MRResultIterator
protected class	MapTask.MapOutputBuffer.SpillThread

Nested classes/interfaces inherited from interface org.apache.hadoop.mapred.MapOutputCollector

MapOutputCollector.Context

Constructor Summary

MapTask.MapOutputBuffer()

Method Summary

void	close()
void	collect(K key, V value, int partition) Serialize the key, value to intermediate storage.
int	compare(int mi, int mj) Compare logical range, st i, j MOD offset capacity.
void	flush()
void	init(MapOutputCollector.Context context)
void	swap(int mi, int mj) Swap metadata for items i, j

Methods inherited from class java.lang.Object

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

Constructor Detail

MapTask.MapOutputBuffer

public MapTask.MapOutputBuffer()

Method Detail

init

public void init(MapOutputCollector.Context context)
          throws IOException,
                 ClassNotFoundException

Specified by:

init in interface MapOutputCollector<K,V>

Throws:

IOException

ClassNotFoundException

collect

public void collect(K key,
                    V value,
                    int partition)
             throws IOException

Serialize the key, value to intermediate storage. When this method returns, kvindex must refer to sufficient unused storage to store one METADATA.

Specified by:

collect in interface MapOutputCollector<K,V>

Throws:

IOException

compare

public int compare(int mi,
                   int mj)

Compare logical range, st i, j MOD offset capacity. Compare by partition, then by key.

Specified by:

compare in interface org.apache.hadoop.util.IndexedSortable

See Also:

IndexedSortable.compare(int, int)

swap

public void swap(int mi,
                 int mj)

Swap metadata for items i, j

Specified by:

swap in interface org.apache.hadoop.util.IndexedSortable

See Also:

IndexedSortable.swap(int, int)

flush

public void flush()
           throws IOException,
                  ClassNotFoundException,
                  InterruptedException

Specified by:

flush in interface MapOutputCollector<K,V>

Throws:

IOException

ClassNotFoundException

InterruptedException

close

public void close()

Specified by:

close in interface MapOutputCollector<K,V>