com.splout.db.hadoop
Class SumReducer
java.lang.Object
com.datasalt.pangool.tuplemr.TupleReducer<com.datasalt.pangool.io.ITuple,org.apache.hadoop.io.NullWritable>
com.splout.db.hadoop.SumReducer
- All Implemented Interfaces:
- java.io.Serializable
public class SumReducer
- extends com.datasalt.pangool.tuplemr.TupleReducer<com.datasalt.pangool.io.ITuple,org.apache.hadoop.io.NullWritable>
Reusable TupleReducer that aggregates the counts of a certain field in the Tuple.
There are nicer implementations of this in the work-in-progress Pangool-flow project of Pangool but I decided not to
depend on it until it has a first stable version.
- See Also:
- Serialized Form
Nested classes/interfaces inherited from class com.datasalt.pangool.tuplemr.TupleReducer |
com.datasalt.pangool.tuplemr.TupleReducer.Collector, com.datasalt.pangool.tuplemr.TupleReducer.CombinerCollector, com.datasalt.pangool.tuplemr.TupleReducer.StaticCollector<OUTPUT_KEY,OUTPUT_VALUE,CONTEXT_OUTPUT_KEY,CONTEXT_OUTPUT_VALUE>, com.datasalt.pangool.tuplemr.TupleReducer.TupleMRContext |
Constructor Summary |
SumReducer(java.lang.String field)
Will (int) sum the field "field" |
Method Summary |
void |
reduce(com.datasalt.pangool.io.ITuple group,
java.lang.Iterable<com.datasalt.pangool.io.ITuple> tuples,
com.datasalt.pangool.tuplemr.TupleReducer.TupleMRContext context,
com.datasalt.pangool.tuplemr.TupleReducer.Collector collector)
|
Methods inherited from class com.datasalt.pangool.tuplemr.TupleReducer |
cleanup, setup |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
SumReducer
public SumReducer(java.lang.String field)
- Will (int) sum the field "field"
reduce
public void reduce(com.datasalt.pangool.io.ITuple group,
java.lang.Iterable<com.datasalt.pangool.io.ITuple> tuples,
com.datasalt.pangool.tuplemr.TupleReducer.TupleMRContext context,
com.datasalt.pangool.tuplemr.TupleReducer.Collector collector)
throws java.io.IOException,
java.lang.InterruptedException,
com.datasalt.pangool.tuplemr.TupleMRException
- Overrides:
reduce
in class com.datasalt.pangool.tuplemr.TupleReducer<com.datasalt.pangool.io.ITuple,org.apache.hadoop.io.NullWritable>
- Throws:
java.io.IOException
java.lang.InterruptedException
com.datasalt.pangool.tuplemr.TupleMRException
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