com.google.appengine.tools.mapreduce.mappers

Class IdentityMapper<K,V>

java.lang.Object

com.google.appengine.tools.mapreduce.Worker<C>

com.google.appengine.tools.mapreduce.Mapper<KeyValue<K,V>,K,V>

com.google.appengine.tools.mapreduce.mappers.IdentityMapper<K,V>

Type Parameters:

K - the type of the key

V - the type of the value

All Implemented Interfaces:

Serializable

public class IdentityMapper<K,V>
extends Mapper<KeyValue<K,V>,K,V>

A mapper that passes an incoming KeyValue to it's output.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
IdentityMapper()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	emit(O value) Syntactic sugar for getContext().emit(value)
void	map(KeyValue<K,V> input) Processes a single input value, emitting output through the context returned by Worker.getContext() or emit(O).

Methods inherited from class com.google.appengine.tools.mapreduce.Mapper

emit

Methods inherited from class com.google.appengine.tools.mapreduce.Worker

allowSliceRetry, beginShard, beginSlice, endShard, endSlice, estimateMemoryRequirement, getContext, setContext

Methods inherited from class java.lang.Object

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

Constructor Detail

IdentityMapper

public IdentityMapper()

Method Detail

map

public void map(KeyValue<K,V> input)

Processes a single input value, emitting output through the context returned by Worker.getContext() or emit(O).

emit

protected void emit(O value)

Syntactic sugar for getContext().emit(value)