org.apache.hadoop.hbase.mapreduce

Class IdentityTableMapper

java.lang.Object

org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.hbase.io.ImmutableBytesWritable,org.apache.hadoop.hbase.client.Result,KEYOUT,VALUEOUT>

org.apache.hadoop.hbase.mapreduce.TableMapper<org.apache.hadoop.hbase.io.ImmutableBytesWritable,org.apache.hadoop.hbase.client.Result>

org.apache.hadoop.hbase.mapreduce.IdentityTableMapper

@InterfaceAudience.Public
public class IdentityTableMapper
extends TableMapper<org.apache.hadoop.hbase.io.ImmutableBytesWritable,org.apache.hadoop.hbase.client.Result>

Pass the given key and record as-is to the reduce phase.

Nested Class Summary

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

org.apache.hadoop.mapreduce.Mapper.Context

Constructor Summary

Constructors

Constructor and Description
IdentityTableMapper()

Method Summary

Modifier and Type	Method and Description
static void	initJob(String table, org.apache.hadoop.hbase.client.Scan scan, Class<? extends TableMapper> mapper, org.apache.hadoop.mapreduce.Job job) Use this before submitting a TableMap job.
void	map(org.apache.hadoop.hbase.io.ImmutableBytesWritable key, org.apache.hadoop.hbase.client.Result value, org.apache.hadoop.mapreduce.Mapper.Context context) Pass the key, value to reduce.

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

cleanup, run, setup

Methods inherited from class java.lang.Object

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

Constructor Detail

IdentityTableMapper

public IdentityTableMapper()

Method Detail

initJob

public static void initJob(String table,
                           org.apache.hadoop.hbase.client.Scan scan,
                           Class<? extends TableMapper> mapper,
                           org.apache.hadoop.mapreduce.Job job)
                    throws IOException

Use this before submitting a TableMap job. It will appropriately set up the job.

Parameters:

table - The table name.

scan - The scan with the columns to scan.

mapper - The mapper class.

job - The job configuration.

Throws:

IOException - When setting up the job fails.

map

public void map(org.apache.hadoop.hbase.io.ImmutableBytesWritable key,
                org.apache.hadoop.hbase.client.Result value,
                org.apache.hadoop.mapreduce.Mapper.Context context)
         throws IOException,
                InterruptedException

Pass the key, value to reduce.

Overrides:

map in class org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.hbase.io.ImmutableBytesWritable,org.apache.hadoop.hbase.client.Result,org.apache.hadoop.hbase.io.ImmutableBytesWritable,org.apache.hadoop.hbase.client.Result>

Parameters:

key - The current key.

value - The current value.

context - The current context.

Throws:

IOException - When writing the record fails.

InterruptedException - When the job is aborted.