Class DoubleLastValueAggregator

java.lang.Object

io.opentelemetry.sdk.metrics.internal.aggregator.DoubleLastValueAggregator

All Implemented Interfaces:

Aggregator<DoublePointData, DoubleExemplarData>

@ThreadSafe
public final class DoubleLastValueAggregator
extends Object
implements Aggregator<DoublePointData, DoubleExemplarData>

Aggregator that aggregates recorded values by storing the last recorded value.

Limitation: The current implementation does not store a time when the value was recorded, so merging multiple LastValueAggregators will not preserve the ordering of records. This is not a problem because LastValueAggregator is currently only available for Observers which record all values once.

This class is internal and is hence not for public use. Its APIs are unstable and can change at any time.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static final class	DoubleLastValueAggregator.Handle

Field Summary

Fields

Modifier and Type	Field	Description
private final MemoryMode	memoryMode
private final Supplier<ExemplarReservoir<DoubleExemplarData>>	reservoirSupplier

Constructor Summary

Constructors

Constructor	Description
DoubleLastValueAggregator(Supplier<ExemplarReservoir<DoubleExemplarData>> reservoirSupplier, MemoryMode memoryMode)

Method Summary

Modifier and Type	Method	Description
void	copyPoint(DoublePointData point, DoublePointData toReusablePoint)	Copies point into toReusablePoint.
AggregatorHandle<DoublePointData, DoubleExemplarData>	createHandle()	Returns a new AggregatorHandle.
DoublePointData	createReusablePoint()	Creates a new reusable point.
DoublePointData	diff(DoublePointData previous, DoublePointData current)	Returns a new DELTA point by computing the difference between two cumulative points.
void	diffInPlace(DoublePointData previousReusable, DoublePointData current)	Resets one reusable point to be a DELTA point by computing the difference between two cumulative points.
MetricData	toMetricData(Resource resource, InstrumentationScopeInfo instrumentationScopeInfo, MetricDescriptor descriptor, Collection<DoublePointData> points, AggregationTemporality temporality)	Returns the MetricData that this Aggregation will produce.
DoublePointData	toPoint(Measurement measurement)	Return a new point representing the measurement.
void	toPoint(Measurement measurement, DoublePointData reusablePoint)	Resets reusablePoint to represent the measurement.

Methods inherited from class Object

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

Field Details

reservoirSupplier

private final Supplier<ExemplarReservoir<DoubleExemplarData>> reservoirSupplier

memoryMode

private final MemoryMode memoryMode

Constructor Details

DoubleLastValueAggregator

public DoubleLastValueAggregator(Supplier<ExemplarReservoir<DoubleExemplarData>> reservoirSupplier,
 MemoryMode memoryMode)

Method Details

createHandle

public AggregatorHandle<DoublePointData, DoubleExemplarData> createHandle()

Description copied from interface: Aggregator

Returns a new AggregatorHandle. This MUST by used by the synchronous to aggregate recorded measurements during the collection cycle.

Specified by:

createHandle in interface Aggregator<DoublePointData, DoubleExemplarData>

Returns:

a new AggregatorHandle.

diff

public DoublePointData diff(DoublePointData previous,
 DoublePointData current)

Description copied from interface: Aggregator

Returns a new DELTA point by computing the difference between two cumulative points.

Aggregators MUST implement diff if it can be used with asynchronous instruments.

Specified by:

diff in interface Aggregator<DoublePointData, DoubleExemplarData>

Parameters:

previous - the previously captured point.

current - the newly captured (cumulative) point.

Returns:

The resulting delta point.

diffInPlace

public void diffInPlace(DoublePointData previousReusable,
 DoublePointData current)

Description copied from interface: Aggregator

Resets one reusable point to be a DELTA point by computing the difference between two cumulative points.

The delta between the two points is set on previousCumulativeReusable

Aggregators MUST implement diff if it can be used with asynchronous instruments.

Specified by:

diffInPlace in interface Aggregator<DoublePointData, DoubleExemplarData>

Parameters:

previousReusable - the previously captured point.

current - the newly captured (cumulative) point.

toPoint

public DoublePointData toPoint(Measurement measurement)

Description copied from interface: Aggregator

Return a new point representing the measurement.

Aggregators MUST implement diff if it can be used with asynchronous instruments.

Specified by:

toPoint in interface Aggregator<DoublePointData, DoubleExemplarData>

toPoint

public void toPoint(Measurement measurement,
 DoublePointData reusablePoint)

Description copied from interface: Aggregator

Resets reusablePoint to represent the measurement.

Aggregators MUST implement diff if it can be used with asynchronous instruments.

Specified by:

toPoint in interface Aggregator<DoublePointData, DoubleExemplarData>

createReusablePoint

public DoublePointData createReusablePoint()

Description copied from interface: Aggregator

Creates a new reusable point.

Specified by:

createReusablePoint in interface Aggregator<DoublePointData, DoubleExemplarData>

copyPoint

public void copyPoint(DoublePointData point,
 DoublePointData toReusablePoint)

Description copied from interface: Aggregator

Copies point into toReusablePoint.

Specified by:

copyPoint in interface Aggregator<DoublePointData, DoubleExemplarData>

toMetricData

public MetricData toMetricData(Resource resource,
 InstrumentationScopeInfo instrumentationScopeInfo,
 MetricDescriptor descriptor,
 Collection<DoublePointData> points,
 AggregationTemporality temporality)

Description copied from interface: Aggregator

Returns the MetricData that this Aggregation will produce.

Specified by:

toMetricData in interface Aggregator<DoublePointData, DoubleExemplarData>

Parameters:

resource - the resource producing the metric.

instrumentationScopeInfo - the scope that instrumented the metric.

descriptor - the name, description and unit of the metric.

points - list of points

temporality - the temporality of the metric.

Returns:

the MetricDataType that this Aggregation will produce.