eu.dicodeproject.analysis.histogram
Class DateHistogramReducer

java.lang.Object
  org.apache.hadoop.mapreduce.Reducer<KEYIN,VALUEIN,KEYOUT,org.apache.hadoop.io.Writable>
      org.apache.hadoop.hbase.mapreduce.TableReducer<org.apache.hadoop.io.Text,org.apache.hadoop.io.IntWritable,org.apache.hadoop.io.Text>
          eu.dicodeproject.analysis.histogram.DateHistogramReducer

public class DateHistogramReducer
extends org.apache.hadoop.hbase.mapreduce.TableReducer<org.apache.hadoop.io.Text,org.apache.hadoop.io.IntWritable,org.apache.hadoop.io.Text>

Sums all the values coming from the mapper. Splits the key and writes the first part as column qualifier and the second part as row key. The sum of values is the cell value.

Nested Class Summary

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

org.apache.hadoop.mapreduce.Reducer.Context

Constructor Summary

DateHistogramReducer()

Method Summary

protected void

reduce(org.apache.hadoop.io.Text keyin, Iterable<org.apache.hadoop.io.IntWritable> values, org.apache.hadoop.mapreduce.Reducer.Context context) Add up data and write to table.

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

cleanup, run, setup

Methods inherited from class java.lang.Object

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

Constructor Detail

DateHistogramReducer

public DateHistogramReducer()

Method Detail

reduce

protected void reduce(org.apache.hadoop.io.Text keyin,
                      Iterable<org.apache.hadoop.io.IntWritable> values,
                      org.apache.hadoop.mapreduce.Reducer.Context context)
               throws IOException,
                      InterruptedException

Add up data and write to table.

Overrides:

reduce in class org.apache.hadoop.mapreduce.Reducer<org.apache.hadoop.io.Text,org.apache.hadoop.io.IntWritable,org.apache.hadoop.io.Text,org.apache.hadoop.io.Writable>

Throws:

IOException

InterruptedException