com.google.cloud.dataflow.sdk.util

Class CounterAggregator<InputT,AccumT,OutputT>

java.lang.Object

com.google.cloud.dataflow.sdk.util.CounterAggregator<InputT,AccumT,OutputT>

Type Parameters:

InputT - the type of input values

AccumT - the type of accumulator values

OutputT - the type of output value

All Implemented Interfaces:

Aggregator<InputT,OutputT>

public class CounterAggregator<InputT,AccumT,OutputT>
extends Object
implements Aggregator<InputT,OutputT>

An implementation of the Aggregator interface that uses a Counter as the underlying representation. Supports Combine.CombineFns from the Sum, Min and Max classes.

Constructor Summary

Constructors

Constructor and Description
CounterAggregator(String name, Combine.CombineFn<? super InputT,AccumT,OutputT> combiner, CounterSet.AddCounterMutator addCounterMutator) Constructs a new aggregator with the given name and aggregation logic specified in the CombineFn argument.

Method Summary

Modifier and Type	Method and Description
void	addValue(InputT value) Adds a new value into the Aggregator.
Combine.CombineFn<InputT,?,OutputT>	getCombineFn() Returns the Combine.CombineFn, which combines input elements in the aggregator.
String	getName() Returns the name of the Aggregator.

Methods inherited from class java.lang.Object

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

Constructor Detail

CounterAggregator

public CounterAggregator(String name,
                         Combine.CombineFn<? super InputT,AccumT,OutputT> combiner,
                         CounterSet.AddCounterMutator addCounterMutator)

Constructs a new aggregator with the given name and aggregation logic specified in the CombineFn argument. The underlying counter is automatically added into the provided CounterSet.

If a counter with the same name already exists, it will be reused, as long as it has the same type.

Method Detail

addValue

public void addValue(InputT value)

Description copied from interface: Aggregator

Adds a new value into the Aggregator.

Specified by:

addValue in interface Aggregator<InputT,OutputT>

getName

public String getName()

Description copied from interface: Aggregator

Returns the name of the Aggregator.

Specified by:

getName in interface Aggregator<InputT,OutputT>

getCombineFn

public Combine.CombineFn<InputT,?,OutputT> getCombineFn()

Description copied from interface: Aggregator

Returns the Combine.CombineFn, which combines input elements in the aggregator.

Specified by:

getCombineFn in interface Aggregator<InputT,OutputT>