Package org.apache.storm.streams.operations.aggregators

Class LongSum

java.lang.Object

org.apache.storm.streams.operations.aggregators.LongSum

All Implemented Interfaces:

Serializable, CombinerAggregator<Number,Long,Long>, Operation

public class LongSum
extends Object
implements CombinerAggregator<Number,Long,Long>

Computes the long sum of the input values.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
LongSum()

Method Summary

Modifier and Type	Method	Description
Long	apply(Long aggregate, Number value)	Updates the accumulator by applying the current accumulator with the value.
Long	init()	The initial value of the accumulator to start with.
Long	merge(Long accum1, Long accum2)	Merges two accumulators and returns the merged accumulator.
Long	result(Long accum)	Produces a result value out of the accumulator.

Methods inherited from class java.lang.Object

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

Constructor Detail

LongSum

public LongSum()

Method Detail

init

public Long init()

Description copied from interface: CombinerAggregator

The initial value of the accumulator to start with.

Specified by:

init in interface CombinerAggregator<Number,Long,Long>

Returns:

the initial value of the accumulator

apply

public Long apply(Long aggregate,
                  Number value)

Description copied from interface: CombinerAggregator

Updates the accumulator by applying the current accumulator with the value.

Specified by:

apply in interface CombinerAggregator<Number,Long,Long>

Parameters:

aggregate - the current accumulator

value - the value

Returns:

the updated accumulator

merge

public Long merge(Long accum1,
                  Long accum2)

Description copied from interface: CombinerAggregator

Merges two accumulators and returns the merged accumulator.

Specified by:

merge in interface CombinerAggregator<Number,Long,Long>

Parameters:

accum1 - the first accumulator

accum2 - the second accumulator

Returns:

the merged accumulator

result

public Long result(Long accum)

Description copied from interface: CombinerAggregator

Produces a result value out of the accumulator.

Specified by:

result in interface CombinerAggregator<Number,Long,Long>

Parameters:

accum - the accumulator

Returns:

the result