com.google.cloud.dataflow.sdk.io

Class CountingInput.UnboundedCountingInput

java.lang.Object

com.google.cloud.dataflow.sdk.transforms.PTransform<PBegin,PCollection<Long>>

com.google.cloud.dataflow.sdk.io.CountingInput.UnboundedCountingInput

All Implemented Interfaces:

HasDisplayData, Serializable

Enclosing class:

CountingInput

public static class CountingInput.UnboundedCountingInput
extends PTransform<PBegin,PCollection<Long>>

A PTransform that will produce numbers starting from 0 up to Long.MAX_VALUE.

After Long.MAX_VALUE, the transform never produces more output. (In practice, this limit should never be reached.)

Elements in the resulting PCollection<Long> will by default have timestamps corresponding to processing time at element generation, provided by Instant.now(). Use the transform returned by withTimestampFn(SerializableFunction) to control the output timestamps.

See Also:

Serialized Form

Field Summary

Fields inherited from class com.google.cloud.dataflow.sdk.transforms.PTransform

name

Method Summary

Modifier and Type	Method and Description
PCollection<Long>	apply(PBegin begin) Applies this PTransform on the given InputT, and returns its Output.
CountingInput.UnboundedCountingInput	withMaxNumRecords(long maxRecords) Returns an CountingInput.UnboundedCountingInput like this one, but that will read at most the specified number of elements.
CountingInput.UnboundedCountingInput	withMaxReadTime(Duration readTime) Returns an CountingInput.UnboundedCountingInput like this one, but that will read for at most the specified amount of time.
CountingInput.UnboundedCountingInput	withTimestampFn(SerializableFunction<Long,Instant> timestampFn) Returns an CountingInput.UnboundedCountingInput like this one, but where output elements have the timestamp specified by the timestampFn.

Methods inherited from class com.google.cloud.dataflow.sdk.transforms.PTransform

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

withTimestampFn

public CountingInput.UnboundedCountingInput withTimestampFn(SerializableFunction<Long,Instant> timestampFn)

Returns an CountingInput.UnboundedCountingInput like this one, but where output elements have the timestamp specified by the timestampFn.

Note that the timestamps produced by timestampFn may not decrease.

withMaxNumRecords

public CountingInput.UnboundedCountingInput withMaxNumRecords(long maxRecords)

Returns an CountingInput.UnboundedCountingInput like this one, but that will read at most the specified number of elements.

A bounded amount of elements will be produced by the result transform, and the result PCollection will be bounded.

withMaxReadTime

public CountingInput.UnboundedCountingInput withMaxReadTime(Duration readTime)

Returns an CountingInput.UnboundedCountingInput like this one, but that will read for at most the specified amount of time.

A bounded amount of elements will be produced by the result transform, and the result PCollection will be bounded.

apply

public PCollection<Long> apply(PBegin begin)

Description copied from class: PTransform

Applies this PTransform on the given InputT, and returns its Output.

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).

The default implementation throws an exception. A derived class must either implement apply, or else each runner must supply a custom implementation via PipelineRunner.apply(com.google.cloud.dataflow.sdk.transforms.PTransform<InputT, OutputT>, InputT).

Overrides:

apply in class PTransform<PBegin,PCollection<Long>>