de.hpi.fgis.voidgen.hadoop.tasks.inputstatistics
Class Task1Reducer
java.lang.Object
org.apache.hadoop.mapreduce.Reducer<org.apache.hadoop.io.Text,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.NullWritable>
de.hpi.fgis.voidgen.hadoop.tasks.inputstatistics.Task1Reducer
public class Task1Reducer
- extends org.apache.hadoop.mapreduce.Reducer<org.apache.hadoop.io.Text,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.NullWritable>
Counts each distinct key.
Input
- Key: prefixed subject, object, predicate or context
- Value: ignored
Output
- nothing will be emitted
- the output is represented by the
Task1Counter
s
- Author:
- Dandy Fenz, Hasso Plattner Institute at University of Potsdam, Germany, Matthias Pohl, Hasso Plattner Institute at University of Potsdam, Germany, Johannes Gosda, Hasso Plattner Institute at University of Potsdam, Germany
Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.Reducer |
org.apache.hadoop.mapreduce.Reducer.Context |
Method Summary |
void |
reduce(org.apache.hadoop.io.Text key,
java.lang.Iterable<org.apache.hadoop.io.NullWritable> 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 |
Task1Reducer
public Task1Reducer()
reduce
public void reduce(org.apache.hadoop.io.Text key,
java.lang.Iterable<org.apache.hadoop.io.NullWritable> values,
org.apache.hadoop.mapreduce.Reducer.Context context)
throws java.io.IOException,
java.lang.InterruptedException
- Overrides:
reduce
in class org.apache.hadoop.mapreduce.Reducer<org.apache.hadoop.io.Text,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.NullWritable,org.apache.hadoop.io.NullWritable>
- Throws:
java.io.IOException
java.lang.InterruptedException