fish.payara.monitoring.model

Class ConstantDataset

java.lang.Object

fish.payara.monitoring.model.SeriesDataset

fish.payara.monitoring.model.ConstantDataset

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

StableDataset

public class ConstantDataset
extends SeriesDataset

A special SeriesDataset for Series for only same value was observed so far. The main advantage over a PartialDataset is the low memory footprint and overall smaller object size for values that do not change anyway. Should they change the add(long, long) method returns a PartialDataset. A minor second advantage is that the observed span can have any length and still be represented with just two points. So in contrast to a PartialDataset which only has information for a fixed sliding time-frame the constant nature allows the ConstantDataset to span any time-frame giving the user a more information while using less resources. Last but not least the ConstantDataset does not risk to become PartialDataset.isOutdated().

Author:

Jan Bernitt

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ConstantDataset(EmptyDataset predecessor, long time, long value)
ConstantDataset(SeriesDataset predecessor, long time)

Method Summary

Modifier and Type	Method and Description
SeriesDataset	add(long time, long value)
int	capacity()
int	estimatedBytesMemory()
long	firstTime()
long	getObservedMax()
long	getObservedMin()
BigInteger	getObservedSum()
int	getObservedValueChanges() Note that minimum is 1 (changing from unknown to know value).
int	getStableCount()
long	getStableSince()
boolean	isOutdated()
long	lastTime()
long	lastValue()
long[]	points() Example:
int	size()

Methods inherited from class fish.payara.monitoring.model.SeriesDataset

equals, getInstance, getObservedAvg, getObservedSince, getObservedValues, getSeries, hashCode, isStable, isStableZero, perSecond, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

ConstantDataset

public ConstantDataset(SeriesDataset predecessor,
                       long time)

ConstantDataset

public ConstantDataset(EmptyDataset predecessor,
                       long time,
                       long value)

Method Detail

points

public long[] points()

Description copied from class: SeriesDataset

Example:

 [t0, v0, t1, v1, t2, v2]
 

Specified by:

points in class SeriesDataset

Returns:

this dataset as flat array with alternating time and value data.

add

public SeriesDataset add(long time,
                         long value)

Specified by:

add in class SeriesDataset

getObservedMin

public long getObservedMin()

Specified by:

getObservedMin in class SeriesDataset

Returns:

The smallest value observed so far. If no value was observed Long.MAX_VALUE.

getObservedMax

public long getObservedMax()

Specified by:

getObservedMax in class SeriesDataset

Returns:

The largest value observed so far. If no value was observed Long.MIN_VALUE.

getObservedSum

public BigInteger getObservedSum()

Specified by:

getObservedSum in class SeriesDataset

Returns:

sum of all observed values.

getObservedValueChanges

public int getObservedValueChanges()

Description copied from class: SeriesDataset

Note that minimum is 1 (changing from unknown to know value). Zero means no values have been observed yet. Note also that change count of 1 does not imply that the value never did change just that such a change was never observed.

Specified by:

getObservedValueChanges in class SeriesDataset

Returns:

Number of times the value as altered since it has been monitored.

getStableSince

public long getStableSince()

Specified by:

getStableSince in class SeriesDataset

Returns:

the time of the first value that is still same as SeriesDataset.lastValue().

getStableCount

public int getStableCount()

Specified by:

getStableCount in class SeriesDataset

Returns:

the number of recent observed points that all had the same value which is same as SeriesDataset.lastValue()

isOutdated

public final boolean isOutdated()

Specified by:

isOutdated in class SeriesDataset

Returns:

true in case data sharing with updated sets has caused this set to be outdated. This practically does not happen if the sets are used as intended and usually suggests misuse of a programming mistake.

size

public final int size()

Specified by:

size in class SeriesDataset

Returns:

the number of actual points in the dataset. This is not the number of observed points but the number of points still known.

firstTime

public final long firstTime()

Specified by:

firstTime in class SeriesDataset

Returns:

the time value of the first of the SeriesDataset.points()

lastTime

public final long lastTime()

Specified by:

lastTime in class SeriesDataset

Returns:

the time value of the last of the SeriesDataset.points()

lastValue

public final long lastValue()

Specified by:

lastValue in class SeriesDataset

Returns:

the value of the last of the SeriesDataset.points()

capacity

public final int capacity()

Specified by:

capacity in class SeriesDataset

Returns:

the maximum number of points in a dataset before adding a new point does remove the oldest point

estimatedBytesMemory

public int estimatedBytesMemory()

Specified by:

estimatedBytesMemory in class SeriesDataset

Returns:

the estimated memory in bytes used by this dataset. Since the object layout in memory is a JVM internal this is only a rough estimation based on the fields. References are assumed to use 8 bytes. Padding is not included.