org.apache.hadoop.hbase.mapred
Class TableMap

java.lang.Object
  extended by org.apache.hadoop.mapred.MapReduceBase
      extended by org.apache.hadoop.hbase.mapred.TableMap
All Implemented Interfaces:
Closeable, JobConfigurable, Mapper
Direct Known Subclasses:
GroupingTableMap, IdentityTableMap

public abstract class TableMap
extends MapReduceBase
implements Mapper

Scan an HBase table to sort by a specified sort column. If the column does not exist, the record is not passed to Reduce.


Constructor Summary
TableMap()
          constructor
 
Method Summary
static void initJob(String table, String columns, Class<? extends TableMap> mapper, JobConf job)
          Use this before submitting a TableMap job.
abstract  void map(HStoreKey key, MapWritable value, TableOutputCollector output, Reporter reporter)
          Call a user defined function on a single HBase record, represented by a key and its associated record value.
 void map(WritableComparable key, Writable value, OutputCollector output, Reporter reporter)
          Input:
 
Methods inherited from class org.apache.hadoop.mapred.MapReduceBase
close, configure
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 
Methods inherited from interface org.apache.hadoop.mapred.JobConfigurable
configure
 
Methods inherited from interface org.apache.hadoop.io.Closeable
close
 

Constructor Detail

TableMap

public TableMap()
constructor

Method Detail

initJob

public static void initJob(String table,
                           String columns,
                           Class<? extends TableMap> mapper,
                           JobConf job)
Use this before submitting a TableMap job. It will appropriately set up the JobConf.

Parameters:
table - table name
columns - columns to scan
mapper - mapper class
job - job configuration

map

public void map(WritableComparable key,
                Writable value,
                OutputCollector output,
                Reporter reporter)
         throws IOException
Input:

Specified by:
map in interface Mapper
Parameters:
key - is of type HStoreKey
value - is of type KeyedDataArrayWritable
output - output collector
reporter - object to use for status updates
Throws:
IOException - Output: The key is a specific column, including the input key or any value The value is of type LabeledData

map

public abstract void map(HStoreKey key,
                         MapWritable value,
                         TableOutputCollector output,
                         Reporter reporter)
                  throws IOException
Call a user defined function on a single HBase record, represented by a key and its associated record value.

Parameters:
key -
value -
output -
reporter -
Throws:
IOException


Copyright © 2006 The Apache Software Foundation