net.i2p.stat

Class Frequency

java.lang.Object

net.i2p.stat.Frequency

public class Frequency
extends Object

Manage the calculation of a moving average event frequency over a certain period. This provides lifetime, and rolling average, frequency counts. Unlike Rate, it does not support "bucketed" averages. There is no tracking of the event frequency in the current or last bucket. There are no buckets at all. Depending on what you want, a rolling average might be better than buckets. Or not.

Constructor Summary

Constructors

Constructor and Description
Frequency(long period)

Method Summary

Modifier and Type	Method and Description
void	eventOccurred() Take note that a new event occurred, recalculating all the averages and frequencies
double	getAverageEventsPerPeriod() Calculate how many events would occur in a period given the current (rolling) average.
double	getAverageInterval() on average over the last $period, after how many milliseconds are events coming in, as calculated during the last event occurrence?
long	getEventCount() how many events have occurred within the lifetime of this stat?
double	getMaxAverageEventsPerPeriod() Calculate how many events would occur in a period given the maximum rolling average.
long	getPeriod() how long is this frequency averaged over? (ms)
double	getStrictAverageEventsPerPeriod() using the strict average interval, how many events occur within an average period?
double	getStrictAverageInterval() Over the lifetime of this stat, without any decay or weighting, what was the average interval between events? (ms)
void	recalculate() Recalculate the averages
(package private) void	store(StringBuilder dest) Appends the data of this frequency to the specified StringBuilder

Methods inherited from class java.lang.Object

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

Constructor Detail

Frequency

public Frequency(long period)

Parameters:

period - ms

Method Detail

eventOccurred

public void eventOccurred()

Take note that a new event occurred, recalculating all the averages and frequencies

getAverageEventsPerPeriod

public double getAverageEventsPerPeriod()

Calculate how many events would occur in a period given the current (rolling) average. Use getStrictAverageInterval() for the real lifetime average.

getAverageInterval

public double getAverageInterval()

on average over the last $period, after how many milliseconds are events coming in, as calculated during the last event occurrence?

Returns:

milliseconds; returns period + 1 if no events in previous period

getEventCount

public long getEventCount()

how many events have occurred within the lifetime of this stat?

getMaxAverageEventsPerPeriod

public double getMaxAverageEventsPerPeriod()

Calculate how many events would occur in a period given the maximum rolling average. Use getStrictAverageEventsPerPeriod() for the real lifetime average.

getPeriod

public long getPeriod()

how long is this frequency averaged over? (ms)

getStrictAverageEventsPerPeriod

public double getStrictAverageEventsPerPeriod()

using the strict average interval, how many events occur within an average period?

getStrictAverageInterval

public double getStrictAverageInterval()

Over the lifetime of this stat, without any decay or weighting, what was the average interval between events? (ms)

Returns:

milliseconds; returns Double.MAX_VALUE if no events ever

recalculate

public void recalculate()

Recalculate the averages

store

void store(StringBuilder dest)

Appends the data of this frequency to the specified StringBuilder

Parameters:

dest - to append data to