com.google.cloud.dataflow.sdk.transforms.windowing

Class Window.Bound<T>

java.lang.Object

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

com.google.cloud.dataflow.sdk.transforms.windowing.Window.Bound<T>

Type Parameters:

T - The type of elements this Window is applied to

All Implemented Interfaces:

Serializable

Enclosing class:

Window

public static class Window.Bound<T>
extends PTransform<PCollection<T>,PCollection<T>>

A PTransform that windows the elements of a PCollection<T>, into finite windows according to a user-specified WindowFn<T, B>.

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<T>	apply(PCollection<T> input) Applies this PTransform on the given InputT, and returns its Output.
protected Coder<?>	getDefaultOutputCoder(PCollection<T> input) Returns the default Coder to use for the output of this single-output PTransform when applied to the given input.
protected String	getKindString() Returns the name to use by default for this PTransform (not including the names of any enclosing PTransforms).
com.google.cloud.dataflow.sdk.util.WindowingStrategy<? super T,?>	getWindowingStrategy()
Window.Bound<T>	named(String name) Returns a new Window PTransform that's like this PTransform but with the specified name.
Window.Triggering<T>	triggering(Trigger<?> trigger) Sets a non-default trigger for this Window PTransform.
Window.Bound<T>	withAllowedLateness(org.joda.time.Duration allowedLateness) Override the amount of lateness allowed for data elements in the pipeline.

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

getDefaultOutputCoder, getDefaultOutputCoder, getName, toString, validate

Methods inherited from class java.lang.Object

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

Method Detail

named

public Window.Bound<T> named(String name)

Returns a new Window PTransform that's like this PTransform but with the specified name. Does not modify this PTransform.

See the discussion of Naming in ParDo for more explanation.

triggering

@Experimental(value=TRIGGER)
public Window.Triggering<T> triggering(Trigger<?> trigger)

Sets a non-default trigger for this Window PTransform. Elements that are assigned to a specific window will be output when the trigger fires.

Trigger has more details on the available triggers.

withAllowedLateness

@Experimental(value=TRIGGER)
public Window.Bound<T> withAllowedLateness(org.joda.time.Duration allowedLateness)

Override the amount of lateness allowed for data elements in the pipeline. Like the other properties on this Window operation, this will be applied at the next GroupByKey. Any elements that are later than this as decided by the system-maintained watermark will be dropped.

This value also determines how long state will be kept around for old windows. Once no elements will be added to a window (because this duration has passed) any state associated with the window will be cleaned up.

apply

public PCollection<T> apply(PCollection<T> input)

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<PCollection<T>,PCollection<T>>

getDefaultOutputCoder

protected Coder<?> getDefaultOutputCoder(PCollection<T> input)

Description copied from class: PTransform

Returns the default Coder to use for the output of this single-output PTransform when applied to the given input.

Overrides:

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

getWindowingStrategy

public com.google.cloud.dataflow.sdk.util.WindowingStrategy<? super T,?> getWindowingStrategy()

getKindString

protected 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>>