Package org.apache.beam.sdk.transforms

Class ApproximateUnique.Globally<T>

java.lang.Object

org.apache.beam.sdk.transforms.PTransform<PCollection<T>,PCollection<Long>>

org.apache.beam.sdk.transforms.ApproximateUnique.Globally<T>

Type Parameters:

T - the type of the elements in the input PCollection

All Implemented Interfaces:

Serializable, HasDisplayData

Enclosing class:

ApproximateUnique

public static final class ApproximateUnique.Globally<T>
extends PTransform<PCollection<T>,PCollection<Long>>

PTransform for estimating the number of distinct elements in a PCollection.

See Also:

• Serialized Form

Field Summary

Fields inherited from class org.apache.beam.sdk.transforms.PTransform

annotations, displayData, name, resourceHints

Constructor Summary

Constructors

Constructor	Description
Globally(double maximumEstimationError)
Globally(int sampleSize)

Method Summary

Modifier and Type	Method	Description
PCollection<Long>	expand(PCollection<T> input)	Override this method to specify how this PTransform should be expanded on the given InputT.
void	populateDisplayData(DisplayData.Builder builder)	Register display data for the given transform or component.

Methods inherited from class org.apache.beam.sdk.transforms.PTransform

addAnnotation, compose, compose, getAdditionalInputs, getAnnotations, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, getResourceHints, setDisplayData, setResourceHints, toString, validate, validate

Methods inherited from class java.lang.Object

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

Constructor Details

Globally

public Globally(int sampleSize)

See Also:

• ApproximateUnique.globally(int)

Globally

public Globally(double maximumEstimationError)

See Also:

• ApproximateUnique.globally(double)

Method Details

expand

public PCollection<Long> expand(PCollection<T> input)

Description copied from class: PTransform

Override this method to specify how this PTransform should be expanded on the given InputT.

NOTE: This method should not be called directly. Instead apply the PTransform should be applied to the InputT using the apply method.

Composite transforms, which are defined in terms of other transforms, should return the output of one of the composed transforms. Non-composite transforms, which do not apply any transforms internally, should return a new unbound output and register evaluators (via backend-specific registration methods).

Specified by:

expand in class PTransform<PCollection<T>,PCollection<Long>>

populateDisplayData

public void populateDisplayData(DisplayData.Builder builder)

Description copied from class: PTransform

Register display data for the given transform or component.

populateDisplayData(DisplayData.Builder) is invoked by Pipeline runners to collect display data via DisplayData.from(HasDisplayData). Implementations may call super.populateDisplayData(builder) in order to register display data in the current namespace, but should otherwise use subcomponent.populateDisplayData(builder) to use the namespace of the subcomponent.

By default, does not register any display data. Implementors may override this method to provide their own display data.

Specified by:

populateDisplayData in interface HasDisplayData

Overrides:

populateDisplayData in class PTransform<PCollection<T>,PCollection<Long>>

Parameters:

builder - The builder to populate with display data.

See Also:

• HasDisplayData