Package org.opennms.core.ipc.sink.aggregation

Class ArrayListAggregationPolicy<S>

java.lang.Object

org.opennms.core.ipc.sink.aggregation.ArrayListAggregationPolicy<S>

All Implemented Interfaces:

AggregationPolicy<S,List<S>,List<S>>

public class ArrayListAggregationPolicy<S>
extends Object
implements AggregationPolicy<S,List<S>,List<S>>

An aggregation policy that creates ArrayList aggregates.

Author:

Seth

Constructor Summary

Constructors

Constructor	Description
ArrayListAggregationPolicy(int completionSize, int completionInterval, java.util.function.Function<S,Object> keyMapper)

Method Summary

Modifier and Type	Method	Description
List<S>	aggregate(List<S> accumulator, S newMessage)	Aggregate the given message into an existing accumulator, or create a new accumulator if no accumulator exists.
List<S>	build(List<S> accumulator)	Build the resulting message from the accumulator.
int	getCompletionIntervalMs()	Maximum number of milliseconds for which buckets should continue accumulating messages after creation.
int	getCompletionSize()	Maximum number of messages to be added to a bucket before dispatching.
Object	key(S message)	Calculate a key for the given message.

Methods inherited from class java.lang.Object

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

Constructor Detail

ArrayListAggregationPolicy

public ArrayListAggregationPolicy(int completionSize,
                                  int completionInterval,
                                  java.util.function.Function<S,Object> keyMapper)

Method Detail

key

public Object key(S message)

Description copied from interface: AggregationPolicy

Calculate a key for the given message. Objects with the same key will be aggregated together. Returned values should non-null.

Specified by:

key in interface AggregationPolicy<S,List<S>,List<S>>

Parameters:

message - the message

Returns:

the message's key

aggregate

public List<S> aggregate(List<S> accumulator,
                         S newMessage)

Description copied from interface: AggregationPolicy

Aggregate the given message into an existing accumulator, or create a new accumulator if no accumulator exists.

Specified by:

aggregate in interface AggregationPolicy<S,List<S>,List<S>>

Parameters:

accumulator - the existing accumulator, or null if a new accumulator should be created

newMessage - the message to aggregate

Returns:

the new or updated accumulator

build

public List<S> build(List<S> accumulator)

Description copied from interface: AggregationPolicy

Build the resulting message from the accumulator.

Specified by:

build in interface AggregationPolicy<S,List<S>,List<S>>

Parameters:

accumulator - an existing accumulator

Returns:

the aggregated message to dispatch

getCompletionSize

public int getCompletionSize()

Description copied from interface: AggregationPolicy

Maximum number of messages to be added to a bucket before dispatching. If this value is <= 1, the buckets should be dispatched immediately after adding a single element.

Specified by:

getCompletionSize in interface AggregationPolicy<S,List<S>,List<S>>

Returns:

maximum number of messages per bucket

getCompletionIntervalMs

public int getCompletionIntervalMs()

Description copied from interface: AggregationPolicy

Maximum number of milliseconds for which buckets should continue accumulating messages after creation. If a bucket has been created for longer than this interval, it will be dispatched regardless of it's current size. Values <= 0 will disable periodic flushing and buckets will only be dispatched once they have reached the maximum size.

Specified by:

getCompletionIntervalMs in interface AggregationPolicy<S,List<S>,List<S>>

Returns:

number of milliseconds to keep a bucket before dispatching