com.netflix.turbine.data

Class StatsRollingNumber

java.lang.Object

com.netflix.turbine.data.StatsRollingNumber

public class StatsRollingNumber
extends java.lang.Object

A number which can be used to track counters (increment) or set values over time.

It is "rolling" in the sense that a 'timeInMilliseconds' is given that you want to track (such as 10 seconds) and then that is broken into buckets (defaults to 10) so that the 10 second window doesn't empty out and restart every 10 seconds, but instead every 1 second you have a new bucket added and one dropped so that 9 of the buckets remain and only the newest starts from scratch.

This is done so that the statistics are gathered over a rolling 10 second window with data being added/dropped in 1 seconds intervals (or whatever granularity is defined by the arguments) rather than each 10 second window starting at 0 again.

See inner-class UnitTest for usage and expected behavior examples.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StatsRollingNumber.Type
static class	StatsRollingNumber.UnitTest

Constructor Summary

Constructors

Constructor and Description
StatsRollingNumber(com.netflix.config.DynamicIntProperty timeInMilliseconds)
StatsRollingNumber(com.netflix.config.DynamicIntProperty timeInMilliseconds, com.netflix.config.DynamicIntProperty numberOfBuckets)
StatsRollingNumber(int timeInMilliseconds, int numberOfBuckets)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	compareAndSet(StatsRollingNumber.Type type, int expected, int value) A compareAndSet counterpart to set to allow atomically safe updates of an existing value.
int	getCount(StatsRollingNumber.Type type) Get the sum of all buckets in the rolling counter for the given CounterType.
int	getMaxValue(StatsRollingNumber.Type type) Get the max value of values in all buckets for the given CounterType.
int	getMinValue(StatsRollingNumber.Type type) Get the min value of values in all buckets for the given CounterType.
int[]	getModifiedValues(StatsRollingNumber.Type type)
int	getNumberOfBuckets()
int	getRollingTimeInMilliseconds()
int	getSum(StatsRollingNumber.Type type) Get the sum of all buckets in the rolling counter for the given CounterType.
int	getValueOfLatestBucket(StatsRollingNumber.Type type) Get the sum of all buckets in the rolling counter for the given CounterType.
int[]	getValues(StatsRollingNumber.Type type) Get an array of values for all buckets in the rolling counter for the given CounterType.
void	increment(StatsRollingNumber.Type type)
void	increment(StatsRollingNumber.Type type, int delta)
void	reset() Force a reset of all counters (clear all buckets) so that statistics start being gathered from scratch.
void	set(StatsRollingNumber.Type type, int value) A number in a rolling bucket that you can set.

Methods inherited from class java.lang.Object

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

Constructor Detail

StatsRollingNumber

public StatsRollingNumber(com.netflix.config.DynamicIntProperty timeInMilliseconds)

StatsRollingNumber

public StatsRollingNumber(int timeInMilliseconds,
                  int numberOfBuckets)

StatsRollingNumber

public StatsRollingNumber(com.netflix.config.DynamicIntProperty timeInMilliseconds,
                  com.netflix.config.DynamicIntProperty numberOfBuckets)

Method Detail

getNumberOfBuckets

public int getNumberOfBuckets()

getRollingTimeInMilliseconds

public int getRollingTimeInMilliseconds()

increment

public void increment(StatsRollingNumber.Type type)

increment

public void increment(StatsRollingNumber.Type type,
             int delta)

set

public void set(StatsRollingNumber.Type type,
       int value)

A number in a rolling bucket that you can set.

Parameters:

type -

value -

compareAndSet

public boolean compareAndSet(StatsRollingNumber.Type type,
                    int expected,
                    int value)

A compareAndSet counterpart to set to allow atomically safe updates of an existing value.

Will set value to 'value' if 'current value' == 'expected'

Parameters:

type -

expected -

value -

Returns:

true if successful, false means the current actual value was not equal to expected value.

reset

public void reset()

Force a reset of all counters (clear all buckets) so that statistics start being gathered from scratch.

getCount

public int getCount(StatsRollingNumber.Type type)

Get the sum of all buckets in the rolling counter for the given CounterType.

Parameters:

type -

Returns:

int

getSum

public int getSum(StatsRollingNumber.Type type)

Get the sum of all buckets in the rolling counter for the given CounterType.

Parameters:

type -

Returns:

int

getValueOfLatestBucket

public int getValueOfLatestBucket(StatsRollingNumber.Type type)

Get the sum of all buckets in the rolling counter for the given CounterType.

Parameters:

type -

Returns:

int

getValues

public int[] getValues(StatsRollingNumber.Type type)

Get an array of values for all buckets in the rolling counter for the given CounterType.

Index 0 is the oldest bucket.

Parameters:

type -

Returns:

int[]

getModifiedValues

public int[] getModifiedValues(StatsRollingNumber.Type type)

getMaxValue

public int getMaxValue(StatsRollingNumber.Type type)

Get the max value of values in all buckets for the given CounterType.

Parameters:

type -

Returns:

int

getMinValue

public int getMinValue(StatsRollingNumber.Type type)

Get the min value of values in all buckets for the given CounterType.

Parameters:

type -

Returns:

int