org.apache.hadoop.examples
Class QuasiMonteCarlo.QmcReducer
java.lang.Object
org.apache.hadoop.mapreduce.Reducer<org.apache.hadoop.io.BooleanWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.WritableComparable<?>,org.apache.hadoop.io.Writable>
org.apache.hadoop.examples.QuasiMonteCarlo.QmcReducer
- Enclosing class:
- QuasiMonteCarlo
public static class QuasiMonteCarlo.QmcReducer
- extends Reducer<org.apache.hadoop.io.BooleanWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.WritableComparable<?>,org.apache.hadoop.io.Writable>
Reducer class for Pi estimation.
Accumulate points inside/outside results from the mappers.
Method Summary |
void |
cleanup(Reducer.Context context)
Reduce task done, write output to a file. |
void |
reduce(org.apache.hadoop.io.BooleanWritable isInside,
Iterable<org.apache.hadoop.io.LongWritable> values,
Reducer.Context context)
Accumulate number of points inside/outside results from the mappers. |
Methods inherited from class org.apache.hadoop.mapreduce.Reducer |
run, setup |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
QuasiMonteCarlo.QmcReducer
public QuasiMonteCarlo.QmcReducer()
reduce
public void reduce(org.apache.hadoop.io.BooleanWritable isInside,
Iterable<org.apache.hadoop.io.LongWritable> values,
Reducer.Context context)
throws IOException,
InterruptedException
- Accumulate number of points inside/outside results from the mappers.
- Overrides:
reduce
in class Reducer<org.apache.hadoop.io.BooleanWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.WritableComparable<?>,org.apache.hadoop.io.Writable>
- Parameters:
isInside
- Is the points inside?values
- An iterator to a list of point countscontext
- dummy, not used here.
- Throws:
IOException
InterruptedException
cleanup
public void cleanup(Reducer.Context context)
throws IOException
- Reduce task done, write output to a file.
- Overrides:
cleanup
in class Reducer<org.apache.hadoop.io.BooleanWritable,org.apache.hadoop.io.LongWritable,org.apache.hadoop.io.WritableComparable<?>,org.apache.hadoop.io.Writable>
- Throws:
IOException
Copyright © 2009 The Apache Software Foundation