org.apache.hadoop.mapreduce
Interface ReduceContext.ValueIterator<VALUEIN>

All Known Implementing Classes:
ReduceContextImpl.ValueIterator
Enclosing interface:
ReduceContext<KEYIN,VALUEIN,KEYOUT,VALUEOUT>

public static interface ReduceContext.ValueIterator<VALUEIN>

Iterator to iterate over values for a given group of records.


Method Summary
 void clearMark()
          Clear any previously set mark
 void mark()
          Mark the current record.
 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 interface java.util.Iterator
hasNext, next, remove
 

Method Detail

resetBackupStore

void resetBackupStore()
                      throws IOException
This method is called when the reducer moves from one key to another.

Throws:
IOException

mark

void mark()
          throws IOException
Mark the current record. A subsequent call to reset will rewind the iterator to this record.

Throws:
IOException

reset

void reset()
           throws IOException
Reset the iterator to the last record before a call to the previous mark

Throws:
IOException

clearMark

void clearMark()
               throws IOException
Clear any previously set mark

Throws:
IOException


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