org.glassfish.pfl.tf.timer.spi
Class StatisticsAccumulator

java.lang.Object
  org.glassfish.pfl.tf.timer.spi.StatisticsAccumulator

public class StatisticsAccumulator
extends Object

Author:

Hemanth Puttaswamy

StatisticsAccumulator accumulates the samples provided by the user and computes the value of minimum, maximum, sum and sample square sum. When the StatisticMonitoredAttribute calls getValue(), it will compute all the statistics for the collected samples (Which are Minimum, Maximum, Average, StandardDeviation) and provides a nice printable record as a String. Users can easily extend this class and provide the implementation of toString() method to format the stats as desired. By default all the stats are printed in a single line.

Constructor Summary

StatisticsAccumulator(String unit)
Construct the Statistics Accumulator by providing the unit as a String.

Method Summary

void	augment(StatisticsAccumulator acc)
double	average()
void	clearState() Clears the samples and starts fresh on new samples.
long	count()
Statistics	getStats()
String	getValue() Computes the Standard Statistic Results based on the samples collected so far and provides the complete value as a formatted String
double	max()
double	min()
void	sample(double value)
double	standardDeviation()
String	toString() Users can extend StatisticsAccumulator to provide the complete Stats in the format they prefer, if the default format doesn't suffice.
String	unit()
void	unitTestValidate(String expectedUnit, double expectedMin, double expectedMax, long expectedSampleCount, double expectedAverage, double expectedStandardDeviation) This is an internal API to test StatisticsAccumulator...

Methods inherited from class java.lang.Object

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

Constructor Detail

StatisticsAccumulator

public StatisticsAccumulator(String unit)

Construct the Statistics Accumulator by providing the unit as a String. The examples of units are "Hours", "Minutes", "Seconds", "MilliSeconds", "Micro Seconds" etc.,

Parameters:

unit - a String representing the units for the samples collected

Method Detail

unit

public String unit()

count

public long count()

min

public double min()

max

public double max()

average

public double average()

standardDeviation

public double standardDeviation()

sample

public void sample(double value)

getStats

public Statistics getStats()

augment

public void augment(StatisticsAccumulator acc)

getValue

public String getValue()

Computes the Standard Statistic Results based on the samples collected so far and provides the complete value as a formatted String

toString

public String toString()

Users can extend StatisticsAccumulator to provide the complete Stats in the format they prefer, if the default format doesn't suffice.

Overrides:

toString in class Object

clearState

public void clearState()

Clears the samples and starts fresh on new samples.

unitTestValidate

public void unitTestValidate(String expectedUnit,
                             double expectedMin,
                             double expectedMax,
                             long expectedSampleCount,
                             double expectedAverage,
                             double expectedStandardDeviation)

This is an internal API to test StatisticsAccumulator...