com.asakusafw.runtime.flow

Class SegmentedReducer<KEYIN extends SegmentedWritable,VALUEIN extends SegmentedWritable,KEYOUT extends org.apache.hadoop.io.Writable,VALUEOUT extends org.apache.hadoop.io.Writable>

java.lang.Object

org.apache.hadoop.mapreduce.Reducer<KEYIN,VALUEIN,KEYOUT,VALUEOUT>

com.asakusafw.runtime.flow.ReducerWithRuntimeResource<KEYIN,VALUEIN,KEYOUT,VALUEOUT>

com.asakusafw.runtime.flow.SegmentedReducer<KEYIN,VALUEIN,KEYOUT,VALUEOUT>

Type Parameters:

KEYIN - the input key type

VALUEIN - the input value type

KEYOUT - the output key type

VALUEOUT - the output value type

public abstract class SegmentedReducer<KEYIN extends SegmentedWritable,VALUEIN extends SegmentedWritable,KEYOUT extends org.apache.hadoop.io.Writable,VALUEOUT extends org.apache.hadoop.io.Writable>
extends ReducerWithRuntimeResource<KEYIN,VALUEIN,KEYOUT,VALUEOUT>

A skeletal implementation of Hadoop Reducer class which uses SegmentedWritable as it input key/value.

Since:

0.1.0

Version:

0.5.1

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.Reducer

org.apache.hadoop.mapreduce.Reducer.Context

Field Summary

Fields

Modifier and Type	Field and Description
static String	GET_RENDEZVOUS The method name of getRendezvous(SegmentedWritable).

Constructor Summary

Constructors

Constructor and Description
SegmentedReducer()

Method Summary

Modifier and Type	Method and Description
protected abstract Rendezvous<VALUEIN>	getRendezvous(KEYIN key) Returns the Rendezvous object for processing the target segment.
protected void	reduce(KEYIN key, Iterable<VALUEIN> values, org.apache.hadoop.mapreduce.Reducer.Context context)

Methods inherited from class com.asakusafw.runtime.flow.ReducerWithRuntimeResource

run, runInternal

Methods inherited from class org.apache.hadoop.mapreduce.Reducer

cleanup, setup

Methods inherited from class java.lang.Object

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

Field Detail

GET_RENDEZVOUS

public static final String GET_RENDEZVOUS

The method name of getRendezvous(SegmentedWritable).

See Also:

Constant Field Values

Constructor Detail

SegmentedReducer

public SegmentedReducer()

Method Detail

getRendezvous

protected abstract Rendezvous<VALUEIN> getRendezvous(KEYIN key)

Returns the Rendezvous object for processing the target segment.

Parameters:

key - the segment information

Returns:

the corresponded Rendezvous object

reduce

protected void reduce(KEYIN key,
                      Iterable<VALUEIN> values,
                      org.apache.hadoop.mapreduce.Reducer.Context context)
               throws IOException,
                      InterruptedException

Overrides:

reduce in class org.apache.hadoop.mapreduce.Reducer<KEYIN extends SegmentedWritable,VALUEIN extends SegmentedWritable,KEYOUT extends org.apache.hadoop.io.Writable,VALUEOUT extends org.apache.hadoop.io.Writable>

Throws:

IOException

InterruptedException