org.apache.datasketches.pig.frequencies

Class DataToFrequentItemsSketch<T>

java.lang.Object

org.apache.pig.EvalFunc<org.apache.pig.data.Tuple>

org.apache.datasketches.pig.frequencies.DataToFrequentItemsSketch<T>

Type Parameters:

T - type of item

All Implemented Interfaces:

org.apache.pig.Accumulator<org.apache.pig.data.Tuple>

Direct Known Subclasses:

DataToFrequentStringsSketch

public abstract class DataToFrequentItemsSketch<T>
extends org.apache.pig.EvalFunc<org.apache.pig.data.Tuple>
implements org.apache.pig.Accumulator<org.apache.pig.data.Tuple>

This is a generic implementation to be specialized in concrete UDFs

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.pig.EvalFunc

org.apache.pig.EvalFunc.SchemaType

Field Summary

Fields inherited from class org.apache.pig.EvalFunc

log, pigLogger, reporter, returnType

Constructor Summary

Constructors

Constructor and Description
DataToFrequentItemsSketch(int sketchSize, org.apache.datasketches.ArrayOfItemsSerDe<T> serDe) Constructs a function given a sketch size and serde

Method Summary

Modifier and Type	Method and Description
void	accumulate(org.apache.pig.data.Tuple inputTuple)
void	cleanup()
org.apache.pig.data.Tuple	exec(org.apache.pig.data.Tuple inputTuple)
org.apache.pig.data.Tuple	getValue()

Methods inherited from class org.apache.pig.EvalFunc

allowCompileTimeCalculation, finish, getArgToFuncMapping, getCacheFiles, getInputSchema, getLoadCaster, getLogger, getPigLogger, getReporter, getReturnType, getSchemaName, getSchemaType, getShipFiles, isAsynchronous, needEndOfAllInputProcessing, outputSchema, progress, setEndOfAllInput, setInputSchema, setPigLogger, setReporter, setUDFContextSignature, warn

Methods inherited from class java.lang.Object

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

Constructor Detail

DataToFrequentItemsSketch

public DataToFrequentItemsSketch(int sketchSize,
                                 org.apache.datasketches.ArrayOfItemsSerDe<T> serDe)

Constructs a function given a sketch size and serde

Parameters:

sketchSize - parameter controlling the size of the sketch and the accuracy

serDe - an instance of ArrayOfItemsSerDe to serialize and deserialize arrays of items

Method Detail

accumulate

public void accumulate(org.apache.pig.data.Tuple inputTuple)
                throws IOException

Specified by:

accumulate in interface org.apache.pig.Accumulator<org.apache.pig.data.Tuple>

Throws:

IOException

cleanup

public void cleanup()

Specified by:

cleanup in interface org.apache.pig.Accumulator<org.apache.pig.data.Tuple>

getValue

public org.apache.pig.data.Tuple getValue()

Specified by:

getValue in interface org.apache.pig.Accumulator<org.apache.pig.data.Tuple>

exec

public org.apache.pig.data.Tuple exec(org.apache.pig.data.Tuple inputTuple)
                               throws IOException

Specified by:

exec in class org.apache.pig.EvalFunc<org.apache.pig.data.Tuple>

Throws:

IOException