de.hpi.fgis.voidgen.hadoop.closure
Class Step1Reducer

java.lang.Object
  extended by org.apache.hadoop.mapreduce.Reducer<Step1Pair,ClusterId,ClusterId,NodeXOrId>
      extended by de.hpi.fgis.voidgen.hadoop.closure.Step1Reducer

public class Step1Reducer
extends org.apache.hadoop.mapreduce.Reducer<Step1Pair,ClusterId,ClusterId,NodeXOrId>

Applies the current smallest cluster identifier to each vertex and each other cluster identifier that describes the same cluster. Prepares the key-value pairs for the second step of transitive closure generation (merging clusters).

Author:
Johannes Gosda, Hasso Plattner Institute at University of Potsdam, Germany

Nested Class Summary
 
Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.Reducer
org.apache.hadoop.mapreduce.Reducer.Context
 
Constructor Summary
Step1Reducer()
           
 
Method Summary
 void reduce(Step1Pair key, java.lang.Iterable<ClusterId> values, org.apache.hadoop.mapreduce.Reducer.Context context)
           
 
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

Step1Reducer

public Step1Reducer()
Method Detail

reduce

public void reduce(Step1Pair key,
                   java.lang.Iterable<ClusterId> values,
                   org.apache.hadoop.mapreduce.Reducer.Context context)
            throws java.io.IOException,
                   java.lang.InterruptedException
Overrides:
reduce in class org.apache.hadoop.mapreduce.Reducer<Step1Pair,ClusterId,ClusterId,NodeXOrId>
Throws:
java.io.IOException
java.lang.InterruptedException