Package org.apache.beam.sdk.transforms

Class View.AsList<T>

java.lang.Object

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

org.apache.beam.sdk.transforms.View.AsList<T>

All Implemented Interfaces:

Serializable, HasDisplayData

Enclosing class:

View

@Internal
public static class View.AsList<T>
extends PTransform<PCollection<T>,PCollectionView<List<T>>>

For internal use only; no backwards-compatibility guarantees.

Public only so a PipelineRunner may override its behavior.

See View.asList().

See Also:

• Serialized Form

Field Summary

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

annotations, displayData, name, resourceHints

Method Summary

Modifier and Type	Method	Description
PCollectionView<List<T>>	expand(PCollection<T> input)	Override this method to specify how this PTransform should be expanded on the given InputT.
View.AsList<T>	inMemory()	Returns a PCollection view like this one, but whose resulting list will be entirely cached in memory.
View.AsList<T>	inMemory(boolean inMemory)	Returns a PCollection view like this one, but whose resulting list will be entirely cached in memory according to the input parameter.
View.AsList<T>	withRandomAccess()	Returns a PCollection view like this one, but whose resulting list will have RandomAccess (aka fast indexing).
View.AsList<T>	withRandomAccess(boolean withRandomAccess)	Returns a PCollection view like this one, but whose resulting list will have RandomAccess (aka fast indexing) according to the input parameter.

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

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

Methods inherited from class java.lang.Object

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

Method Details

withRandomAccess

public View.AsList<T> withRandomAccess()

Returns a PCollection view like this one, but whose resulting list will have RandomAccess (aka fast indexing).

A veiw with random access will be much more expensive to compute and iterate over, but will have a faster get() method.

withRandomAccess

public View.AsList<T> withRandomAccess(boolean withRandomAccess)

Returns a PCollection view like this one, but whose resulting list will have RandomAccess (aka fast indexing) according to the input parameter.

A veiw with random access will be much more expensive to compute and iterate over, but will have a faster get() method.

inMemory

public View.AsList<T> inMemory()

Returns a PCollection view like this one, but whose resulting list will be entirely cached in memory.

This may use more memory in exchange for the fastest access when used repeatedly.

inMemory

public View.AsList<T> inMemory(boolean inMemory)

Returns a PCollection view like this one, but whose resulting list will be entirely cached in memory according to the input parameter.

This may use more memory in exchange for the fastest access when used repeatedly.

expand

public PCollectionView<List<T>> 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>,PCollectionView<List<T>>>