com.hp.sdn.metric

Class TimeStampedHistogram

java.lang.Object

com.codahale.metrics.Histogram

com.hp.sdn.metric.TimeStampedHistogram

All Implemented Interfaces:

com.codahale.metrics.Counting, com.codahale.metrics.Metric, com.codahale.metrics.Sampling, TimeStampedMetric

public class TimeStampedHistogram
extends com.codahale.metrics.Histogram
implements TimeStampedMetric

Extension of Coda Hale Histogram class that provides an association of sliding time window Histogram values with time stamps.

Author:

Steve Britt

Constructor Summary

Constructors

Constructor and Description
TimeStampedHistogram(MetricRegistry registry, HistogramDescriptor descriptor) Constructs a TimeStampedHistogram with the specified characteristics using the specified MetricRegistry.
TimeStampedHistogram(MetricRegistry registry, HistogramDescriptor descriptor, String uid) Constructs a TimeStampedHistogram with the specified UID and other characteristics using the specified MetricRegistry.

Method Summary

Methods

Modifier and Type	Method and Description
HistogramDataPoint	extractDataPoint() Extract a HistogramDataPoint from this object.
double	get75thPercentile() Gets the value at the 75th percentile of all values currently encompassed within the the sliding time window of this TimeStampedHistogram.
double	get95thPercentile() Gets the value at the 95th percentile of all values currently encompassed within the the sliding time window of this TimeStampedHistogram.
double	get98thPercentile() Gets the value at the 98th percentile of all values currently encompassed within the the sliding time window of this TimeStampedHistogram.
double	get99thPercentile() Gets the value at the 99th percentile of all values currently encompassed within the the sliding time window of this TimeStampedHistogram.
long	getCount()
HistogramDescriptor	getDescriptor() Gets the MetricDescriptor that describes this TimeStampedMetric object.
long	getMaximum() Gets the maximum of all values currently encompassed within the sliding time window of this TimeStampedHistogram.
double	getMean() Gets the mean of the values currently encompassed within the sliding time window of this TimeStampedHistogram.
double	getMedian() Gets the median of all values currently encompassed within the sliding time window of this TimeStampedHistogram.
long	getMinimum() Gets the minimum of all values currently encompassed within the sliding time window of this TimeStampedHistogram.
long	getMsSpanned() Determines the number of milliseconds spanned between the latest (update) time stamp and the oldest (previous) time stamp, accounting for roll-over of the time stamp.
long	getPreviousTimeStamp() Gets the previous time stamp.
int	getSlidingWindowMinutes() Gets the number of minutes spanned by the sliding time window of this TimeStampedHistogram.
double	getStandardDeviation() Gets the standard deviation of the values currently encompassed within the sliding time window of this TimeStampedHistogram.
protected TimeStampManager	getTimeStampManager() Gets the TimeStampManager that this object uses to manage its associated time stamps.
String	getUid() Gets the UID.
long	getUpdateTimeStamp() Gets the update time stamp.
long[]	getValues() Gets the actual values currently encompassed within the sliding time window of this TimeStampedHistogram.
boolean	isValid() Indicates whether this TimeStampedMetric's current value is a valid one.
void	reset() Prepares the histogram for use in a new time period.
void	setDescriptor(HistogramDescriptor toSet) Sets the HistogramDescriptor that specifies characteristics of this TimeStampedHistogram.
void	setPreviousTimeStamp(long time) Sets the previous time stamp.
void	setUid(String toSet) Sets the UID of this object.
void	setUpdateTimeStamp(long time) Sets the update time stamp.
String	toDebugString() Gets a detailed representation of this object to facilitate debugging.
String	toString()
void	update(int toAdd)
void	update(long toAdd)
void	updateTimeStamp() Convenience method that sets the update time stamp to the current time.

Methods inherited from class com.codahale.metrics.Histogram

getSnapshot

Methods inherited from class java.lang.Object

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

Constructor Detail

TimeStampedHistogram

public TimeStampedHistogram(MetricRegistry registry,
                    HistogramDescriptor descriptor)

Constructs a TimeStampedHistogram with the specified characteristics using the specified MetricRegistry.

Parameters:

registry - MetricRegistry to use for allocating this object

descriptor - HistogramDescriptor that specifies various characteristics of the resulting TimeStampedHistogram

TimeStampedHistogram

public TimeStampedHistogram(MetricRegistry registry,
                    HistogramDescriptor descriptor,
                    String uid)

Constructs a TimeStampedHistogram with the specified UID and other characteristics using the specified MetricRegistry.

Parameters:

registry - MetricRegistry to use for allocating this object

descriptor - HistogramDescriptor that specifies various characteristics of the resulting TimeStampedHistogram

uid - UID to assign to the resulting TimeStampedHistogram

Throws:

IllegalArgumentException - if a null value is supplied for either the HistogramDescriptor or MetricRegistry argument

Method Detail

extractDataPoint

public HistogramDataPoint extractDataPoint()

Extract a HistogramDataPoint from this object.

Specified by:

extractDataPoint in interface TimeStampedMetric

Returns:

the current value of this object represented as a HistogramDataPoint

get75thPercentile

public double get75thPercentile()

Gets the value at the 75th percentile of all values currently encompassed within the the sliding time window of this TimeStampedHistogram.

Returns:

value at 75th percentile

get95thPercentile

public double get95thPercentile()

Gets the value at the 95th percentile of all values currently encompassed within the the sliding time window of this TimeStampedHistogram.

Returns:

value at 95th percentile

get98thPercentile

public double get98thPercentile()

Gets the value at the 98th percentile of all values currently encompassed within the the sliding time window of this TimeStampedHistogram.

Returns:

value at 98th percentile

get99thPercentile

public double get99thPercentile()

Gets the value at the 99th percentile of all values currently encompassed within the the sliding time window of this TimeStampedHistogram.

Returns:

value at 99th percentile

getCount

public long getCount()

Specified by:

getCount in interface com.codahale.metrics.Counting

Overrides:

getCount in class com.codahale.metrics.Histogram

getDescriptor

public HistogramDescriptor getDescriptor()

Description copied from interface: TimeStampedMetric

Gets the MetricDescriptor that describes this TimeStampedMetric object.

Specified by:

getDescriptor in interface TimeStampedMetric

Returns:

MetricDescriptor that describes this TimeStampedMetric

getMaximum

public long getMaximum()

Gets the maximum of all values currently encompassed within the sliding time window of this TimeStampedHistogram.

Returns:

maximum of histogram values

getMedian

public double getMedian()

Gets the median of all values currently encompassed within the sliding time window of this TimeStampedHistogram.

Returns:

median value (value at 50th percentile)

getMean

public double getMean()

Gets the mean of the values currently encompassed within the sliding time window of this TimeStampedHistogram.

Returns:

mean of histogram values

getMinimum

public long getMinimum()

Gets the minimum of all values currently encompassed within the sliding time window of this TimeStampedHistogram.

Returns:

minimum of histogram values

getMsSpanned

public long getMsSpanned()

Description copied from interface: TimeStampedMetric

Determines the number of milliseconds spanned between the latest (update) time stamp and the oldest (previous) time stamp, accounting for roll-over of the time stamp.

Specified by:

getMsSpanned in interface TimeStampedMetric

Returns:

milliseconds spanned between the update and previous time stamps

getPreviousTimeStamp

public long getPreviousTimeStamp()

Description copied from interface: TimeStampedMetric

Gets the previous time stamp.

Specified by:

getPreviousTimeStamp in interface TimeStampedMetric

Returns:

previous time stamp

getSlidingWindowMinutes

public int getSlidingWindowMinutes()

Gets the number of minutes spanned by the sliding time window of this TimeStampedHistogram.

Returns:

minutes in sliding window

getStandardDeviation

public double getStandardDeviation()

Gets the standard deviation of the values currently encompassed within the sliding time window of this TimeStampedHistogram.

Returns:

standard deviation of histogram values

getTimeStampManager

protected TimeStampManager getTimeStampManager()

Gets the TimeStampManager that this object uses to manage its associated time stamps.

Returns:

the TimeStampManager for this object

getUid

public String getUid()

Description copied from interface: TimeStampedMetric

Gets the UID.

Specified by:

getUid in interface TimeStampedMetric

Returns:

the UID

getUpdateTimeStamp

public long getUpdateTimeStamp()

Description copied from interface: TimeStampedMetric

Gets the update time stamp.

Specified by:

getUpdateTimeStamp in interface TimeStampedMetric

Returns:

update time stamp

getValues

public long[] getValues()

Gets the actual values currently encompassed within the sliding time window of this TimeStampedHistogram.

Returns:

histogram values

isValid

public boolean isValid()

Description copied from interface: TimeStampedMetric

Indicates whether this TimeStampedMetric's current value is a valid one. For example, it could be a non-numeric value like Double.NaN, depending upon type and state of the TimeStampedMetric.

Specified by:

isValid in interface TimeStampedMetric

Returns:

true if valid, false otherwise

reset

public void reset()

Prepares the histogram for use in a new time period. There is no way to clear the histogram, so just reset the span of time it will cover when it is next analyzed as starting at the current time. Set both the update and previous time stamps to the current time.

Specified by:

reset in interface TimeStampedMetric

setDescriptor

public void setDescriptor(HistogramDescriptor toSet)

Sets the HistogramDescriptor that specifies characteristics of this TimeStampedHistogram.

Parameters:

toSet - the HistogramDescriptor for this object

setPreviousTimeStamp

public void setPreviousTimeStamp(long time)

Description copied from interface: TimeStampedMetric

Sets the previous time stamp.

Specified by:

setPreviousTimeStamp in interface TimeStampedMetric

Parameters:

time - previous time stamp

setUid

public void setUid(String toSet)

Description copied from interface: TimeStampedMetric

Sets the UID of this object.

Specified by:

setUid in interface TimeStampedMetric

Parameters:

toSet - new UID for this object

setUpdateTimeStamp

public void setUpdateTimeStamp(long time)

Description copied from interface: TimeStampedMetric

Sets the update time stamp.

Specified by:

setUpdateTimeStamp in interface TimeStampedMetric

Parameters:

time - update time stamp

toDebugString

public String toDebugString()

Gets a detailed representation of this object to facilitate debugging.

Returns:

debug representation of object

toString

public String toString()

Overrides:

toString in class Object

update

public void update(int toAdd)

Overrides:

update in class com.codahale.metrics.Histogram

update

public void update(long toAdd)

Overrides:

update in class com.codahale.metrics.Histogram

updateTimeStamp

public void updateTimeStamp()

Description copied from interface: TimeStampedMetric

Convenience method that sets the update time stamp to the current time.

Specified by:

updateTimeStamp in interface TimeStampedMetric