io.opentelemetry.sdk.trace

Class Samplers

java.lang.Object

io.opentelemetry.sdk.trace.Samplers

@Immutable
public final class Samplers
extends Object

Static class to access a set of pre-defined Samplers.

Method Summary

Modifier and Type	Method and Description
static Sampler	alwaysOff() Returns a Sampler that always makes a "no" Sampler.SamplingResult for Span sampling.
static Sampler	alwaysOn() Returns a Sampler that always makes a "yes" Sampler.SamplingResult for Span sampling.
static Sampler.SamplingResult	emptySamplingResult(Sampler.Decision decision) Returns a Sampler.SamplingResult with empty attributes and Sampler.SamplingResult.getDecision() returning decision.
static Sampler	parentBased(Sampler root) Returns a Sampler that always makes the same decision as the parent Span to whether or not to sample.
static io.opentelemetry.sdk.trace.Samplers.ParentBased.Builder	parentBasedBuilder(Sampler root) Returns a ParentBased.Builder that follows the parent's sampling decision if one exists, otherwise following the root sampler and other optional sampler's decision.
static Sampler.SamplingResult	samplingResult(Sampler.Decision decision, io.opentelemetry.common.Attributes attributes) Returns a Sampler.SamplingResult with the given attributes and Sampler.SamplingResult.getDecision() returning decision.
static Sampler	traceIdRatioBased(double ratio) Returns a new TraceIdRatioBased Sampler.

Methods inherited from class java.lang.Object

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

Method Detail

samplingResult

public static Sampler.SamplingResult samplingResult(Sampler.Decision decision,
                                                    io.opentelemetry.common.Attributes attributes)

Returns a Sampler.SamplingResult with the given attributes and Sampler.SamplingResult.getDecision() returning decision.

This is meant for use by custom Sampler implementations.

Using #emptySamplingResult(Decision) instead of this method is slightly faster and shorter if you don't need attributes.

Parameters:

decision - The decision made on the span.

attributes - The attributes to return from Sampler.SamplingResult.getAttributes(). A different object instance with the same elements may be returned.

Returns:

A Sampler.SamplingResult with the attributes equivalent to attributes and the provided decision.

emptySamplingResult

public static Sampler.SamplingResult emptySamplingResult(Sampler.Decision decision)

Returns a Sampler.SamplingResult with empty attributes and Sampler.SamplingResult.getDecision() returning decision.

This is meant for use by custom Sampler implementations.

Use #samplingResult(Decision, Attributes) if you need attributes.

Parameters:

decision - The decision made on the span.

Returns:

A Sampler.SamplingResult with empty attributes and the provided decision.

alwaysOn

public static Sampler alwaysOn()

Returns a Sampler that always makes a "yes" Sampler.SamplingResult for Span sampling.

Returns:

a Sampler that always makes a "yes" Sampler.SamplingResult for Span sampling.

alwaysOff

public static Sampler alwaysOff()

Returns a Sampler that always makes a "no" Sampler.SamplingResult for Span sampling.

Returns:

a Sampler that always makes a "no" Sampler.SamplingResult for Span sampling.

parentBased

public static Sampler parentBased(Sampler root)

Returns a Sampler that always makes the same decision as the parent Span to whether or not to sample. If there is no parent, the Sampler uses the provided Sampler delegate to determine the sampling decision.

Parameters:

root - the Sampler which is used to make the sampling decisions if the parent does not exist.

Returns:

a Sampler that follows the parent's sampling decision if one exists, otherwise following the root sampler's decision.

parentBasedBuilder

public static io.opentelemetry.sdk.trace.Samplers.ParentBased.Builder parentBasedBuilder(Sampler root)

Returns a ParentBased.Builder that follows the parent's sampling decision if one exists, otherwise following the root sampler and other optional sampler's decision.

Parameters:

root - the required Sampler which is used to make the sampling decisions if the parent does not exist.

Returns:

a ParentBased.Builder

traceIdRatioBased

public static Sampler traceIdRatioBased(double ratio)

Returns a new TraceIdRatioBased Sampler. The ratio of sampling a trace is equal to that of the specified ratio.

Parameters:

ratio - The desired ratio of sampling. Must be within [0.0, 1.0].

Returns:

a new TraceIdRatioBased Sampler.

Throws:

IllegalArgumentException - if ratio is out of range