co.cask.cdap.etl.api.batch

Interface BatchAggregatorContext

All Superinterfaces:

BatchContext, DatasetContext, LookupProvider, StageContext, TransformContext

@Beta
public interface BatchAggregatorContext
extends BatchContext

Context of a Batch Aggregator.

Method Summary

Methods

Modifier and Type	Method and Description
void	setGroupKeyClass(Class<?> groupKeyClass) Set the group key class.
void	setGroupValueClass(Class<?> groupValueClass) Set the group value class.
void	setNumPartitions(int numPartitions) Set the number of partitions to use to group values.

Methods inherited from interface co.cask.cdap.etl.api.batch.BatchContext

createDataset, datasetExists, getHadoopJob, getLogicalStartTime, getRuntimeArguments, setRuntimeArgument

Methods inherited from interface co.cask.cdap.api.data.DatasetContext

discardDataset, getDataset, getDataset, getDataset, getDataset, releaseDataset

Methods inherited from interface co.cask.cdap.etl.api.StageContext

getMetrics, getPluginProperties, getPluginProperties, getStageName, loadPluginClass, newPluginInstance

Methods inherited from interface co.cask.cdap.etl.api.LookupProvider

provide

Method Detail

setNumPartitions

void setNumPartitions(int numPartitions)

Set the number of partitions to use to group values. If none is set, the execution engine will decide how many partitions to use.

Parameters:

numPartitions - the number of partitions to use when grouping.

setGroupKeyClass

void setGroupKeyClass(Class<?> groupKeyClass)

Set the group key class. This is not required if the aggregator is parameterized with a concrete class for the group key. This method is required if the group key class is only known at configure time versus compile time. For example, an aggregator may support grouping on a configurable record field, and not know the type of that field until configure time.

Parameters:

groupKeyClass - the group key class

setGroupValueClass

void setGroupValueClass(Class<?> groupValueClass)

Set the group value class. This is not required if the aggregator is parameterized with a concrete class for the group value. This method is required if the group value class is only known at configure time versus compile time.

Parameters:

groupValueClass - the group value class