org.apache.storm.starter.tools

Class SlotBasedCounter<T>

java.lang.Object

org.apache.storm.starter.tools.SlotBasedCounter<T>

Type Parameters:

T - The type of those objects we want to count.

All Implemented Interfaces:

Serializable

public final class SlotBasedCounter<T>
extends Object
implements Serializable

This class provides per-slot counts of the occurrences of objects.

It can be used, for instance, as a building block for implementing sliding window counting of objects.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
SlotBasedCounter(int numSlots)

Method Summary

Modifier and Type	Method and Description
long	getCount(T obj, int slot)
Map<T,Long>	getCounts()
void	incrementCount(T obj, int slot)
void	wipeSlot(int slot) Reset the slot count of any tracked objects to zero for the given slot.
void	wipeZeros() Remove any object from the counter whose total count is zero (to free up memory).

Methods inherited from class java.lang.Object

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

Constructor Detail

SlotBasedCounter

public SlotBasedCounter(int numSlots)

Method Detail

incrementCount

public void incrementCount(T obj,
                           int slot)

getCount

public long getCount(T obj,
                     int slot)

getCounts

public Map<T,Long> getCounts()

wipeSlot

public void wipeSlot(int slot)

Reset the slot count of any tracked objects to zero for the given slot.

wipeZeros

public void wipeZeros()

Remove any object from the counter whose total count is zero (to free up memory).