org.apache.pig.backend.hadoop.executionengine.mapReduceLayer
Class PigCombiner.Combine

java.lang.Object
  extended by org.apache.hadoop.mapred.MapReduceBase
      extended by org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.PigCombiner.Combine
All Implemented Interfaces:
Closeable, org.apache.hadoop.mapred.JobConfigurable, org.apache.hadoop.mapred.Reducer<PigNullableWritable,NullableTuple,PigNullableWritable,org.apache.hadoop.io.Writable>
Enclosing class:
PigCombiner

public static class PigCombiner.Combine
extends org.apache.hadoop.mapred.MapReduceBase
implements org.apache.hadoop.mapred.Reducer<PigNullableWritable,NullableTuple,PigNullableWritable,org.apache.hadoop.io.Writable>


Constructor Summary
PigCombiner.Combine()
           
 
Method Summary
 void close()
          Will be called once all the intermediate keys and values are processed.
 void configure(org.apache.hadoop.mapred.JobConf jConf)
          Configures the Reduce plan, the POPackage operator and the reporter thread
 byte getKeyType()
           
 boolean processOnePackageOutput(org.apache.hadoop.mapred.OutputCollector<PigNullableWritable,org.apache.hadoop.io.Writable> oc)
           
 void reduce(PigNullableWritable key, Iterator<NullableTuple> tupIter, org.apache.hadoop.mapred.OutputCollector<PigNullableWritable,org.apache.hadoop.io.Writable> oc, org.apache.hadoop.mapred.Reporter reporter)
          The reduce function which packages the key and List <Tuple> into key, Bag<Tuple> after converting Hadoop type key into Pig type.
 void setKeyType(byte keyType)
           
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

PigCombiner.Combine

public PigCombiner.Combine()
Method Detail

configure

public void configure(org.apache.hadoop.mapred.JobConf jConf)
Configures the Reduce plan, the POPackage operator and the reporter thread

Specified by:
configure in interface org.apache.hadoop.mapred.JobConfigurable
Overrides:
configure in class org.apache.hadoop.mapred.MapReduceBase

reduce

public void reduce(PigNullableWritable key,
                   Iterator<NullableTuple> tupIter,
                   org.apache.hadoop.mapred.OutputCollector<PigNullableWritable,org.apache.hadoop.io.Writable> oc,
                   org.apache.hadoop.mapred.Reporter reporter)
            throws IOException
The reduce function which packages the key and List <Tuple> into key, Bag<Tuple> after converting Hadoop type key into Pig type. The package result is either collected as is, if the reduce plan is empty or after passing through the reduce plan.

Specified by:
reduce in interface org.apache.hadoop.mapred.Reducer<PigNullableWritable,NullableTuple,PigNullableWritable,org.apache.hadoop.io.Writable>
Throws:
IOException

processOnePackageOutput

public boolean processOnePackageOutput(org.apache.hadoop.mapred.OutputCollector<PigNullableWritable,org.apache.hadoop.io.Writable> oc)
                                throws IOException
Throws:
IOException

close

public void close()
           throws IOException
Will be called once all the intermediate keys and values are processed. So right place to stop the reporter thread.

Specified by:
close in interface Closeable
Overrides:
close in class org.apache.hadoop.mapred.MapReduceBase
Throws:
IOException

getKeyType

public byte getKeyType()
Returns:
the keyType

setKeyType

public void setKeyType(byte keyType)
Parameters:
keyType - the keyType to set


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