|Constructor and Description|
|Modifier and Type||Method and Description|
This method is called once for each key.
Called once at the start of the task.
public void setup(org.apache.hadoop.mapreduce.Reducer.Context context) throws IOException, InterruptedException
public void reduce(Text key, Iterable<Text> values, org.apache.hadoop.mapreduce.Reducer.Context context) throws IOException, InterruptedException
key- the key is expected to be a Text object, whose prefix indicates the type of aggregation to aggregate the values. In effect, data driven computing is achieved. It is assumed that each aggregator's getReport method emits appropriate output for the aggregator. This may be further customized.
values- the values to be aggregated
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