com.google.cloud.dataflow.sdk.transforms

Class Sum.SumLongFn

java.lang.Object

com.google.cloud.dataflow.sdk.transforms.Combine.CombineFn<Long,long[],Long>

com.google.cloud.dataflow.sdk.transforms.Combine.BinaryCombineLongFn

com.google.cloud.dataflow.sdk.transforms.Sum.SumLongFn

All Implemented Interfaces:

com.google.cloud.dataflow.sdk.util.common.CounterProvider<Long>, Serializable

Enclosing class:

Sum

public static class Sum.SumLongFn
extends Combine.BinaryCombineLongFn
implements com.google.cloud.dataflow.sdk.util.common.CounterProvider<Long>

A SerializableFunction that computes the sum of an Iterable of Longs, useful as an argument to Combine.globally(com.google.cloud.dataflow.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>) or Combine.perKey(com.google.cloud.dataflow.sdk.transforms.SerializableFunction<java.lang.Iterable<V>, V>).

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
SumLongFn()

Method Summary

Modifier and Type	Method and Description
long	apply(long a, long b) Applies the binary operation to the two operands, returning the result.
com.google.cloud.dataflow.sdk.util.common.Counter<Long>	getCounter(String name)
long	identity() Returns the identity element of this operation, i.e.

Methods inherited from class com.google.cloud.dataflow.sdk.transforms.Combine.BinaryCombineLongFn

addInput, createAccumulator, extractOutput, getAccumulatorCoder, getDefaultOutputCoder, mergeAccumulators

Methods inherited from class com.google.cloud.dataflow.sdk.transforms.Combine.CombineFn

apply, asKeyedFn, compact, getOutputType

Methods inherited from class java.lang.Object

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

Constructor Detail

SumLongFn

public SumLongFn()

Method Detail

apply

public long apply(long a,
                  long b)

Description copied from class: Combine.BinaryCombineLongFn

Applies the binary operation to the two operands, returning the result.

Specified by:

apply in class Combine.BinaryCombineLongFn

identity

public long identity()

Description copied from class: Combine.BinaryCombineLongFn

Returns the identity element of this operation, i.e. an element e such that apply(e, x) == apply(x, e) == x for all values of x.

Specified by:

identity in class Combine.BinaryCombineLongFn

getCounter

public com.google.cloud.dataflow.sdk.util.common.Counter<Long> getCounter(String name)

Specified by:

getCounter in interface com.google.cloud.dataflow.sdk.util.common.CounterProvider<Long>

Overrides:

getCounter in class Combine.BinaryCombineLongFn