org.apache.hadoop.hive.ql.udf.generic
Class GenericUDAFAverage.AbstractGenericUDAFAverageEvaluator<TYPE>

java.lang.Object
  org.apache.hadoop.hive.ql.udf.generic.GenericUDAFEvaluator
      org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AbstractGenericUDAFAverageEvaluator<TYPE>

All Implemented Interfaces:

Closeable

Direct Known Subclasses:

GenericUDAFAverage.GenericUDAFAverageEvaluatorDecimal, GenericUDAFAverage.GenericUDAFAverageEvaluatorDouble

Enclosing class:

GenericUDAFAverage

public abstract static class GenericUDAFAverage.AbstractGenericUDAFAverageEvaluator<TYPE>
extends GenericUDAFEvaluator

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hive.ql.udf.generic.GenericUDAFEvaluator

GenericUDAFEvaluator.AbstractAggregationBuffer, GenericUDAFEvaluator.AggregationBuffer, GenericUDAFEvaluator.AggregationType, GenericUDAFEvaluator.Mode

Field Summary

protected PrimitiveObjectInspector	inputOI
protected Object[]	partialResult
protected ObjectInspector	sumFieldOI

Constructor Summary

GenericUDAFAverage.AbstractGenericUDAFAverageEvaluator()

Method Summary

protected abstract void	doIterate(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation, PrimitiveObjectInspector inputOI, Object parameter)
protected abstract void	doMerge(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation, Long partialCount, ObjectInspector sumFieldOI, Object partialSum)
protected abstract void	doReset(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation)
protected abstract Object	doTerminate(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation)
protected abstract void	doTerminatePartial(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation)
protected abstract ObjectInspector	getSumFieldJavaObjectInspector()
protected abstract ObjectInspector	getSumFieldWritableObjectInspector()
ObjectInspector	init(GenericUDAFEvaluator.Mode m, ObjectInspector[] parameters) Initialize the evaluator.
void	iterate(GenericUDAFEvaluator.AggregationBuffer aggregation, Object[] parameters) Iterate through original data.
void	merge(GenericUDAFEvaluator.AggregationBuffer aggregation, Object partial) Merge with partial aggregation result.
void	reset(GenericUDAFEvaluator.AggregationBuffer aggregation) Reset the aggregation.
Object	terminate(GenericUDAFEvaluator.AggregationBuffer aggregation) Get final aggregation result.
Object	terminatePartial(GenericUDAFEvaluator.AggregationBuffer aggregation) Get partial aggregation result.

Methods inherited from class org.apache.hadoop.hive.ql.udf.generic.GenericUDAFEvaluator

aggregate, close, configure, evaluate, getNewAggregationBuffer, isEstimable

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

inputOI

protected transient PrimitiveObjectInspector inputOI

sumFieldOI

protected ObjectInspector sumFieldOI

partialResult

protected transient Object[] partialResult

Constructor Detail

GenericUDAFAverage.AbstractGenericUDAFAverageEvaluator

public GenericUDAFAverage.AbstractGenericUDAFAverageEvaluator()

Method Detail

getSumFieldJavaObjectInspector

protected abstract ObjectInspector getSumFieldJavaObjectInspector()

getSumFieldWritableObjectInspector

protected abstract ObjectInspector getSumFieldWritableObjectInspector()

doIterate

protected abstract void doIterate(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation,
                                  PrimitiveObjectInspector inputOI,
                                  Object parameter)

doMerge

protected abstract void doMerge(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation,
                                Long partialCount,
                                ObjectInspector sumFieldOI,
                                Object partialSum)

doTerminatePartial

protected abstract void doTerminatePartial(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation)

doTerminate

protected abstract Object doTerminate(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation)

doReset

protected abstract void doReset(org.apache.hadoop.hive.ql.udf.generic.GenericUDAFAverage.AverageAggregationBuffer<TYPE> aggregation)
                         throws HiveException

Throws:

HiveException

init

public ObjectInspector init(GenericUDAFEvaluator.Mode m,
                            ObjectInspector[] parameters)
                     throws HiveException

Description copied from class: GenericUDAFEvaluator

Initialize the evaluator.

Overrides:

init in class GenericUDAFEvaluator

Parameters:

m - The mode of aggregation.

parameters - The ObjectInspector for the parameters: In PARTIAL1 and COMPLETE mode, the parameters are original data; In PARTIAL2 and FINAL mode, the parameters are just partial aggregations (in that case, the array will always have a single element).

Returns:

The ObjectInspector for the return value. In PARTIAL1 and PARTIAL2 mode, the ObjectInspector for the return value of terminatePartial() call; In FINAL and COMPLETE mode, the ObjectInspector for the return value of terminate() call. NOTE: We need ObjectInspector[] (in addition to the TypeInfo[] in GenericUDAFResolver) for 2 reasons: 1. ObjectInspector contains more information than TypeInfo; and GenericUDAFEvaluator.init at execution time. 2. We call GenericUDAFResolver.getEvaluator at compilation time,

Throws:

HiveException

reset

public void reset(GenericUDAFEvaluator.AggregationBuffer aggregation)
           throws HiveException

Description copied from class: GenericUDAFEvaluator

Reset the aggregation. This is useful if we want to reuse the same aggregation.

Specified by:

reset in class GenericUDAFEvaluator

Throws:

HiveException

iterate

public void iterate(GenericUDAFEvaluator.AggregationBuffer aggregation,
                    Object[] parameters)
             throws HiveException

Description copied from class: GenericUDAFEvaluator

Iterate through original data.

Specified by:

iterate in class GenericUDAFEvaluator

parameters - The objects of parameters.

Throws:

HiveException

terminatePartial

public Object terminatePartial(GenericUDAFEvaluator.AggregationBuffer aggregation)
                        throws HiveException

Description copied from class: GenericUDAFEvaluator

Get partial aggregation result.

Specified by:

terminatePartial in class GenericUDAFEvaluator

Returns:

partial aggregation result.

Throws:

HiveException

merge

public void merge(GenericUDAFEvaluator.AggregationBuffer aggregation,
                  Object partial)
           throws HiveException

Description copied from class: GenericUDAFEvaluator

Merge with partial aggregation result. NOTE: null might be passed in case there is no input data.

Specified by:

merge in class GenericUDAFEvaluator

partial - The partial aggregation result.

Throws:

HiveException

terminate

public Object terminate(GenericUDAFEvaluator.AggregationBuffer aggregation)
                 throws HiveException

Description copied from class: GenericUDAFEvaluator

Get final aggregation result.

Specified by:

terminate in class GenericUDAFEvaluator

Returns:

final aggregation result.

Throws:

HiveException