org.apache.hadoop.mapreduce.task
Class ReduceContextImpl.ValueIterator

java.lang.Object
  org.apache.hadoop.mapreduce.task.ReduceContextImpl.ValueIterator

All Implemented Interfaces:

ReduceContext.ValueIterator<VALUEIN>

Enclosing class:

ReduceContextImpl<KEYIN,VALUEIN,KEYOUT,VALUEOUT>

protected class ReduceContextImpl.ValueIterator
extends Object
implements ReduceContext.ValueIterator<VALUEIN>

Constructor Summary

protected

ReduceContextImpl.ValueIterator()

Method Summary

void	clearMark() Clear any previously set mark
boolean	hasNext()
void	mark() Mark the current record.
VALUEIN	next()
void	remove()
void	reset() Reset the iterator to the last record before a call to the previous mark
void	resetBackupStore() This method is called when the reducer moves from one key to another.

Methods inherited from class java.lang.Object

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

Constructor Detail

ReduceContextImpl.ValueIterator

protected ReduceContextImpl.ValueIterator()

Method Detail

hasNext

public boolean hasNext()

next

public VALUEIN next()

remove

public void remove()

mark

public void mark()
          throws IOException

Mark the current record. A subsequent call to reset will rewind the iterator to this record.

Throws:

IOException

reset

public void reset()
           throws IOException

Reset the iterator to the last record before a call to the previous mark

Throws:

IOException

clearMark

public void clearMark()
               throws IOException

Clear any previously set mark

Throws:

IOException

resetBackupStore

public void resetBackupStore()
                      throws IOException

This method is called when the reducer moves from one key to another.

Specified by:

resetBackupStore in interface ReduceContext.ValueIterator<VALUEIN>

Throws:

IOException