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

Class MappingAggregationPolicy<S,​T extends Message>

  • All Implemented Interfaces:
    AggregationPolicy<S,​T,​T>
    public abstract class MappingAggregationPolicy<S,​T extends Message>
extends java.lang.Object
implements AggregationPolicy<S,​T,​T>
    An aggregation policy that performs a simple map operation on the given message.
    Author:
    jwhite

    • Method Summary

      All Methods Instance Methods Abstract Methods Concrete Methods 
      Modifier and Type Method Description
      T aggregate​(T oldBucket, S newMessage)
      Aggregate the given message into an existing accumulator, or create a new accumulator if no accumulator exists.
      T build​(T 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.
      java.lang.Object key​(S message)
      Calculate a key for the given message.
      abstract T map​(S message)  

      • Methods inherited from class java.lang.Object

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

    • Constructor Detail

      • MappingAggregationPolicy

        public MappingAggregationPolicy()

    • Method Detail

      • map

        public abstract T map​(S message)

      • key

        public java.lang.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,​T extends Message,​T extends Message>
        Parameters:
        message - the message
        Returns:
        the message's key

      • 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,​T extends Message,​T extends Message>
        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,​T extends Message,​T extends Message>
        Returns:
        number of milliseconds to keep a bucket before dispatching

      • aggregate

        public T aggregate​(T oldBucket,
                   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,​T extends Message,​T extends Message>
        Parameters:
        oldBucket - 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 T build​(T accumulator)
        Description copied from interface: AggregationPolicy
        Build the resulting message from the accumulator.
        Specified by:
        build in interface AggregationPolicy<S,​T extends Message,​T extends Message>
        Parameters:
        accumulator - an existing accumulator
        Returns:
        the aggregated message to dispatch