oracle.spatial.hadoop.vector.join.mapred

Class JoinMapper<K,V>

java.lang.Object

org.apache.hadoop.mapred.MapReduceBase

oracle.spatial.hadoop.vector.join.mapred.JoinMapper<K,V>

Type Parameters:

K - The type of the input keys as read by the internal input format

V - The type of the input values as read by the internal input format

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, org.apache.hadoop.mapred.JobConfigurable, org.apache.hadoop.mapred.Mapper<org.apache.hadoop.io.NullWritable,org.apache.hadoop.mapred.InputSplit,JoinGroupWritable,RecordInfo>

public class JoinMapper<K,V>
extends org.apache.hadoop.mapred.MapReduceBase
implements org.apache.hadoop.mapred.Mapper<org.apache.hadoop.io.NullWritable,org.apache.hadoop.mapred.InputSplit,JoinGroupWritable,RecordInfo>

Maps records from two different data sets to partitions so all the records laying in the same partition can be grouped.
MultipleInputsFileSplitInputFormat needs to be set as the job's input format in order to read two different data sets.
Partitions are read from a previously generated PartitoningResult file which is expected to be found in the distributed cache with the symbolic link ConfigParams.PARTITIONING_RESULT.
For information about generating a PartitioningResult file see Partitioning.

Constructor Summary

Constructors

Constructor and Description
JoinMapper()

Method Summary

Methods

Modifier and Type	Method and Description
void	configure(org.apache.hadoop.mapred.JobConf jobConf)
void	map(org.apache.hadoop.io.NullWritable key, org.apache.hadoop.mapred.InputSplit value, org.apache.hadoop.mapred.OutputCollector<JoinGroupWritable,RecordInfo> output, org.apache.hadoop.mapred.Reporter reporter)

Methods inherited from class org.apache.hadoop.mapred.MapReduceBase

close

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.io.Closeable

close

Constructor Detail

JoinMapper

public JoinMapper()

Method Detail

configure

public void configure(org.apache.hadoop.mapred.JobConf jobConf)

Specified by:

configure in interface org.apache.hadoop.mapred.JobConfigurable

Overrides:

configure in class org.apache.hadoop.mapred.MapReduceBase

map

public void map(org.apache.hadoop.io.NullWritable key,
       org.apache.hadoop.mapred.InputSplit value,
       org.apache.hadoop.mapred.OutputCollector<JoinGroupWritable,RecordInfo> output,
       org.apache.hadoop.mapred.Reporter reporter)
         throws java.io.IOException

Specified by:

map in interface org.apache.hadoop.mapred.Mapper<org.apache.hadoop.io.NullWritable,org.apache.hadoop.mapred.InputSplit,JoinGroupWritable,RecordInfo>

Throws:

java.io.IOException