org.palladiosimulator.experimentanalysis

Class SlidingWindow

java.lang.Object

org.palladiosimulator.commons.designpatterns.AbstractObservable<ISlidingWindowListener>

org.palladiosimulator.experimentanalysis.SlidingWindow

All Implemented Interfaces:

org.palladiosimulator.commons.designpatterns.IAbstractObservable<ISlidingWindowListener>

public abstract class SlidingWindow
extends org.palladiosimulator.commons.designpatterns.AbstractObservable<ISlidingWindowListener>

This class is an implementation of a fixed length sliding window.
Purpose of this window is to collect measurements of a certain kind that occur within the window length. These measurements are written into the window by a SlidingWindowRecorder.
Once the window is full, the window moves forward by a fixed increment and the collected measurements are propagated to all connected ISlidingWindowListeners, e.g., certain SlidingWindowAggregators.
Additionally, each window instance has an attached ISlidingWindowMoveOnStrategy that defines how the collected data (i.e., the measurements) is adjusted when the window moves forward.

Author:

Florian Rosenthal

See Also:

KeepLastElementPriorToLowerBoundStrategy, SlidingWindowAggregator, SlidingWindowUtilizationAggregator

Constructor Summary

Constructors

Constructor and Description
SlidingWindow(javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> windowLength, javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> increment, javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> initialLowerBound, org.palladiosimulator.metricspec.MetricDescription acceptedMetrics, ISlidingWindowMoveOnStrategy moveOnStrategy) Initializes a new instance of the SlidingWindow class with the given parameters.
SlidingWindow(javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> windowLength, javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> increment, org.palladiosimulator.metricspec.MetricDescription acceptedMetrics, ISlidingWindowMoveOnStrategy moveOnStrategy) Initializes a new instance of the SlidingWindow class with the given parameters.
SlidingWindow(javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> windowLength, org.palladiosimulator.metricspec.MetricDescription acceptedMetrics, ISlidingWindowMoveOnStrategy moveOnStrategy) Initializes a new instance of the SlidingWindow class with the given parameters.

Method Summary

Modifier and Type	Method and Description
void	addMeasurement(org.palladiosimulator.measurementframework.MeasuringValue newMeasurement) Adds a new measurement to the data this window collects.
void	addObserver(ISlidingWindowListener arg0) Attaches a ISlidingWindowListener instance to this window. Most commonly, the given listener is a SlidingWindowAggregator.
void	flush() Discards the data (i.e., the measurements) currently collected by this window.
org.palladiosimulator.metricspec.MetricDescription	getAcceptedMetric() Gets the metric this window accepts.
java.util.List<ISlidingWindowListener>	getAttachedObservers() Gets the currently attached observers.
javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration>	getCurrentLowerBound() Gets the current lower (i.e., left) bound of the window.
javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration>	getCurrentUpperBound() Gets the current upper bound of the window.
javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration>	getEffectiveWindowLength() Gets the current, effective window length.
javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration>	getIncrement() Gets the value this window's lower bound is incremented by once the window moves on.
int	getNumberOfElements() Gets the number of currently collected measurements.
boolean	isEmpty() Indicates if there are currently measurements available.

Methods inherited from class org.palladiosimulator.commons.designpatterns.AbstractObservable

getEventDispatcher, getObservers, removeAllObserver, removeObserver

Methods inherited from class java.lang.Object

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

Constructor Detail

SlidingWindow

public SlidingWindow(javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> windowLength,
                     org.palladiosimulator.metricspec.MetricDescription acceptedMetrics,
                     ISlidingWindowMoveOnStrategy moveOnStrategy)

Initializes a new instance of the SlidingWindow class with the given parameters.

Parameters:

windowLength - The length of the window, given in any arbitrary Duration. Additionally, this measure also denotes the window increment.

acceptedMetrics - As each window only accepts measurements that adhere to a certain metric, a MetricDescription of must be specified.

moveOnStrategy - The ISlidingWindowMoveOnStrategy instance that defines how the collected data (i.e., the measurements) is adjusted when the window moves forward.

Throws:

java.lang.IllegalArgumentException - In one of the following cases:

• given window length is negative
• acceptedMetrics or moveOnStrategy is null

See Also:

SlidingWindow(Measure, Measure, MetricDescription, ISlidingWindowMoveOnStrategy)

SlidingWindow

public SlidingWindow(javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> windowLength,
                     javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> increment,
                     org.palladiosimulator.metricspec.MetricDescription acceptedMetrics,
                     ISlidingWindowMoveOnStrategy moveOnStrategy)

Initializes a new instance of the SlidingWindow class with the given parameters.

Parameters:

windowLength - The length of the window, given in any arbitrary Duration.

increment - This Measure indicates the increment by what the window is moved on, given in any arbitrary Duration.

acceptedMetrics - As each window only accepts measurements that adhere to a certain metric, a MetricDescription of must be specified.

moveOnStrategy - The ISlidingWindowMoveOnStrategy instance that defines how the collected data (i.e., the measurements) is adjusted when the window moves forward.

Throws:

java.lang.IllegalArgumentException - In one of the following cases:

• given window length or increment is negative
• acceptedMetrics or moveOnStrategy is null

SlidingWindow

public SlidingWindow(javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> windowLength,
                     javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> increment,
                     javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> initialLowerBound,
                     org.palladiosimulator.metricspec.MetricDescription acceptedMetrics,
                     ISlidingWindowMoveOnStrategy moveOnStrategy)

Initializes a new instance of the SlidingWindow class with the given parameters.

Parameters:

windowLength - The length of the window, given in any arbitrary Duration.

increment - This Measure indicates the increment by what the window is moved on, given in any arbitrary Duration.

initialLowerBound - This Measure indicates the lower bound value at which the algorithm starts aggregating, given in any arbitrary Duration.

acceptedMetrics - As each window only accepts measurements that adhere to a certain metric, a MetricDescription of must be specified.

moveOnStrategy - The ISlidingWindowMoveOnStrategy instance that defines how the collected data (i.e., the measurements) is adjusted when the window moves forward.

Throws:

java.lang.IllegalArgumentException - In one of the following cases:

• given window length or increment is negative
• acceptedMetrics or moveOnStrategy is null

Method Detail

addMeasurement

public void addMeasurement(org.palladiosimulator.measurementframework.MeasuringValue newMeasurement)

Adds a new measurement to the data this window collects.

Parameters:

newMeasurement - The MeasuringValue instance to add.

Throws:

java.lang.IllegalArgumentException - If the given measurement is null or does not adhere to the metric this window accepts.

flush

public final void flush()

Discards the data (i.e., the measurements) currently collected by this window.

getAcceptedMetric

public final org.palladiosimulator.metricspec.MetricDescription getAcceptedMetric()

Gets the metric this window accepts.

Returns:

A MetricDescription denoting the metric this window accepts.

See Also:

SlidingWindow#addMeasurement(Measurement)

getCurrentLowerBound

public final javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> getCurrentLowerBound()

Gets the current lower (i.e., left) bound of the window.

Returns:

A Measure denoting the current upper bound.

See Also:

getEffectiveWindowLength(), getCurrentUpperBound()

getCurrentUpperBound

public javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> getCurrentUpperBound()

Gets the current upper bound of the window.

Returns:

A Measure denoting the current upper bound.

See Also:

SimulationGovernedSlidingWindow#getEffectiveWindowLength()

getEffectiveWindowLength

public javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> getEffectiveWindowLength()

Gets the current, effective window length. Note that the effective window length might be smaller than specified in SlidingWindow(Measure, MetricDescription, ISlidingWindowMoveOnStrategy) or SlidingWindow(Measure, Measure, MetricDescription, ISlidingWindowMoveOnStrategy) .

Returns:

A Measure denoting the instantaneous effective window length.

See Also:

getCurrentUpperBound()

getIncrement

public final javax.measure.Measure<java.lang.Double,javax.measure.quantity.Duration> getIncrement()

Gets the value this window's lower bound is incremented by once the window moves on.

Returns:

A Measure denoting the window increment.

See Also:

SlidingWindow(Measure, MetricDescription, ISlidingWindowMoveOnStrategy), SlidingWindow(Measure, Measure, MetricDescription, ISlidingWindowMoveOnStrategy)

isEmpty

public final boolean isEmpty()

Indicates if there are currently measurements available.

Returns:

false, if yes, otherwise true

getNumberOfElements

public final int getNumberOfElements()

Gets the number of currently collected measurements.

Returns:

A nonnegative value denoting the number of elements.

addObserver

public final void addObserver(ISlidingWindowListener arg0)

Attaches a ISlidingWindowListener instance to this window.
Most commonly, the given listener is a SlidingWindowAggregator.

Specified by:

addObserver in interface org.palladiosimulator.commons.designpatterns.IAbstractObservable<ISlidingWindowListener>

Overrides:

addObserver in class org.palladiosimulator.commons.designpatterns.AbstractObservable<ISlidingWindowListener>

Parameters:

arg0 - The listener to attach.

Throws:

java.lang.IllegalArgumentException - If the given listener is null or expects a metric other than this window's accepted one.

See Also:

ISlidingWindowListener.getExpectedWindowDataMetric()

getAttachedObservers

public final java.util.List<ISlidingWindowListener> getAttachedObservers()

Gets the currently attached observers.

Returns:

An unmodifiable list containing the attached ISlidingWindowListeners.