Class Sampler

java.lang.Object

io.opencensus.trace.Sampler

Direct Known Subclasses:

AlwaysSampleSampler, NeverSampleSampler, ProbabilitySampler

public abstract class Sampler
extends Object

Sampler is used to make decisions on Span sampling.

Since:

0.5

Constructor Summary

Constructors

Constructor	Description
Sampler()

Method Summary

Modifier and Type	Method	Description
abstract String	getDescription()	Returns the description of this Sampler.
abstract boolean	shouldSample(SpanContext parentContext, Boolean hasRemoteParent, TraceId traceId, SpanId spanId, String name, List<Span> parentLinks)	Called during Span creation to make a sampling decision.

Methods inherited from class Object

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

Constructor Details

Sampler

public Sampler()

Method Details

shouldSample

public abstract boolean shouldSample(@Nullable
 SpanContext parentContext,
 @Nullable
 Boolean hasRemoteParent,
 TraceId traceId,
 SpanId spanId,
 String name,
 List<Span> parentLinks)

Called during Span creation to make a sampling decision.

Parameters:

parentContext - the parent span's SpanContext. null if this is a root span.

hasRemoteParent - true if the parent Span is remote. null if this is a root span.

traceId - the TraceId for the new Span. This will be identical to that in the parentContext, unless this is a root span.

spanId - the SpanId for the new Span.

name - the name of the new Span.

parentLinks - the parentLinks associated with the new Span.

Returns:

true if the Span is sampled.

Since:

0.5

getDescription

public abstract String getDescription()

Returns the description of this Sampler. This may be displayed on debug pages or in the logs.

Example: "ProbabilitySampler{0.000100}"

Returns:

the description of this Sampler.

Since:

0.6