Package org.apache.pulsar.functions.windowing.evictors

Class WatermarkCountEvictionPolicy<T>

  • Type Parameters:
    T - the type of event tracked by this policy.
    All Implemented Interfaces:
    EvictionPolicy<T,​org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long>>
    public class WatermarkCountEvictionPolicy<T>
extends java.lang.Object
implements EvictionPolicy<T,​org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long>>
    An eviction policy that tracks count based on watermark ts and evicts events up to the watermark based on a threshold count.

    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected java.util.concurrent.atomic.AtomicLong currentCount  
      protected int threshold  

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      EvictionPolicy.Action evict​(Event<T> event)
      Decides if an event should be expired from the window, processed in the current window or kept for later processing.
      EvictionContext getContext()
      Returns the current context that is part of this eviction policy.
      org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long> getState()
      Return runtime state to be checkpointed by the framework for restoring the eviction policy in case of failures.
      void reset()
      Resets the eviction policy.
      void restoreState​(org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long> state)
      Restore the eviction policy from the state that was earlier checkpointed by the framework.
      void setContext​(EvictionContext context)
      Sets a context in the eviction policy that can be used while evicting the events.
      java.lang.String toString()  
      void track​(Event<T> event)
      Tracks the event to later decide whether EvictionPolicy.evict(Event) should evict it or not.

      • Methods inherited from class java.lang.Object

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

    • Field Detail

      • threshold

        protected final int threshold

      • currentCount

        protected final java.util.concurrent.atomic.AtomicLong currentCount

    • Constructor Detail

      • WatermarkCountEvictionPolicy

        public WatermarkCountEvictionPolicy​(int count)

    • Method Detail

      • evict

        public EvictionPolicy.Action evict​(Event<T> event)
        Description copied from interface: EvictionPolicy
        Decides if an event should be expired from the window, processed in the current window or kept for later processing.
        Specified by:
        evict in interface EvictionPolicy<T,​org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long>>
        Parameters:
        event - the input event
        Returns:
        the EvictionPolicy.Action to be taken based on the input event

      • track

        public void track​(Event<T> event)
        Description copied from interface: EvictionPolicy
        Tracks the event to later decide whether EvictionPolicy.evict(Event) should evict it or not.
        Specified by:
        track in interface EvictionPolicy<T,​org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long>>
        Parameters:
        event - the input event to be tracked

      • getContext

        public EvictionContext getContext()
        Description copied from interface: EvictionPolicy
        Returns the current context that is part of this eviction policy.
        Specified by:
        getContext in interface EvictionPolicy<T,​org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long>>
        Returns:
        the eviction context

      • setContext

        public void setContext​(EvictionContext context)
        Description copied from interface: EvictionPolicy
        Sets a context in the eviction policy that can be used while evicting the events. E.g. For TimeEvictionPolicy, this could be used to set the reference timestamp.
        Specified by:
        setContext in interface EvictionPolicy<T,​org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long>>
        Parameters:
        context - the eviction context

      • reset

        public void reset()
        Description copied from interface: EvictionPolicy
        Resets the eviction policy.
        Specified by:
        reset in interface EvictionPolicy<T,​org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long>>

      • getState

        public org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long> getState()
        Description copied from interface: EvictionPolicy
        Return runtime state to be checkpointed by the framework for restoring the eviction policy in case of failures.
        Specified by:
        getState in interface EvictionPolicy<T,​org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long>>
        Returns:
        the state

      • restoreState

        public void restoreState​(org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long> state)
        Description copied from interface: EvictionPolicy
        Restore the eviction policy from the state that was earlier checkpointed by the framework.
        Specified by:
        restoreState in interface EvictionPolicy<T,​org.apache.commons.lang3.tuple.Pair<java.lang.Long,​java.lang.Long>>
        Parameters:
        state - the state

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object