org.apache.beam.sdk.transforms

Class Tee<T>

java.lang.Object

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

org.apache.beam.sdk.transforms.Tee<T>

Type Parameters:

T - the element type of the input PCollection

All Implemented Interfaces:

java.io.Serializable, HasDisplayData

public class Tee<T>
extends PTransform<PCollection<T>,PCollection<T>>

A PTransform that returns its input, but also applies its input to an auxiliary PTransform, akin to the shell tee command, which is named after the T-splitter used in plumbing.

This can be useful to write out or otherwise process an intermediate transform without breaking the linear flow of a chain of transforms, e.g.

  PCollection<T> input = ... ;
  PCollection<T> result =
      input.apply(...)
     ...
      input.apply(Tee.of(someSideTransform)
     ...
      input.apply(...);
 

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 and Description
PCollection<T>	expand(PCollection<T> input) Override this method to specify how this PTransform should be expanded on the given InputT.
protected java.lang.String	getKindString() Returns the name to use by default for this PTransform (not including the names of any enclosing PTransforms).
static <T> Tee<T>	of(java.util.function.Consumer<PCollection<T>> consumer) Returns a new Tee PTransform that will apply an auxilary transform to the input as well as pass it on.
static <T> Tee<T>	of(PTransform<PCollection<T>,?> consumer) Returns a new Tee PTransform that will apply an auxilary transform to the input as well as pass it on.

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

addAnnotation, compose, compose, getAdditionalInputs, getAnnotations, getDefaultOutputCoder, getDefaultOutputCoder, getDefaultOutputCoder, 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 Detail

of

public static <T> Tee<T> of(PTransform<PCollection<T>,?> consumer)

Returns a new Tee PTransform that will apply an auxilary transform to the input as well as pass it on.

Type Parameters:

T - the type of the elements in the input PCollection.

Parameters:

consumer - An additional PTransform that should process the input PCollection. Its output will be ignored.

of

public static <T> Tee<T> of(java.util.function.Consumer<PCollection<T>> consumer)

Returns a new Tee PTransform that will apply an auxilary transform to the input as well as pass it on.

Type Parameters:

T - the type of the elements in the input PCollection.

Parameters:

consumer - An arbitrary Consumer that will be wrapped in a PTransform and applied to the input. Its output will be ignored.

expand

public PCollection<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>,PCollection<T>>

getKindString

protected java.lang.String getKindString()

Description copied from class: PTransform

Returns the name to use by default for this PTransform (not including the names of any enclosing PTransforms).

By default, returns the base name of this PTransform's class.

The caller is responsible for ensuring that names of applied PTransforms are unique, e.g., by adding a uniquifying suffix when needed.

Overrides:

getKindString in class PTransform<PCollection<T>,PCollection<T>>