org.apache.beam.sdk.transforms

Class PeriodicSequence

java.lang.Object

org.apache.beam.sdk.transforms.PTransform<PCollection<PeriodicSequence.SequenceDefinition>,PCollection<Instant>>

org.apache.beam.sdk.transforms.PeriodicSequence

All Implemented Interfaces:

java.io.Serializable, HasDisplayData

@Experimental(value=SPLITTABLE_DO_FN)
public class PeriodicSequence
extends PTransform<PCollection<PeriodicSequence.SequenceDefinition>,PCollection<Instant>>

A PTransform which generates a sequence of timestamped elements at given runtime intervals.

Transform assigns each element some timestamp and will only output element when worker clock reach given timestamp. Transform will not output elements prior to target time. Transform can output elements at any time after target time.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	PeriodicSequence.OutputRangeTracker
static class	PeriodicSequence.SequenceDefinition

Field Summary

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

name

Method Summary

Modifier and Type	Method and Description
static PeriodicSequence	create()
PCollection<Instant>	expand(PCollection<PeriodicSequence.SequenceDefinition> input) Override this method to specify how this PTransform should be expanded on the given InputT.

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

compose, compose, getAdditionalInputs, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, getKindString, getName, populateDisplayData, toString, validate

Methods inherited from class java.lang.Object

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

Method Detail

create

public static PeriodicSequence create()

expand

public PCollection<Instant> expand(PCollection<PeriodicSequence.SequenceDefinition> 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<PeriodicSequence.SequenceDefinition>,PCollection<Instant>>