org.apache.beam.sdk.transforms.windowing

Class Window.Unbound

java.lang.Object

org.apache.beam.sdk.transforms.windowing.Window.Unbound

Enclosing class:

Window

public static class Window.Unbound
extends Object

An incomplete Window transform, with unbound input/output type.

Before being applied, into(org.apache.beam.sdk.transforms.windowing.WindowFn<? super T, ?>) must be invoked to specify the WindowFn to invoke, which will also bind the input/output type of this PTransform.

Method Summary

Modifier and Type	Method and Description
<T> Window.Bound<T>	accumulatingFiredPanes() Returns a new Window PTransform that uses the registered WindowFn and Triggering behavior, and that accumulates elements in a pane after they are triggered.
<T> Window.Bound<T>	discardingFiredPanes() Returns a new Window PTransform that uses the registered WindowFn and Triggering behavior, and that discards elements in a pane after they are triggered.
<T> Window.Bound<T>	into(WindowFn<? super T,?> fn) Returns a new Window PTransform that's like this transform but that will use the given WindowFn, and that has its input and output types bound.
<T> Window.Bound<T>	triggering(Trigger trigger) Sets a non-default trigger for this Window PTransform.
<T> Window.Bound<T>	withAllowedLateness(Duration allowedLateness) Override the amount of lateness allowed for data elements in the pipeline.
<T> Window.Bound<T>	withAllowedLateness(Duration allowedLateness, Window.ClosingBehavior behavior) Override the amount of lateness allowed for data elements in the pipeline.

Methods inherited from class java.lang.Object

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

Method Detail

into

public <T> Window.Bound<T> into(WindowFn<? super T,?> fn)

Returns a new Window PTransform that's like this transform but that will use the given WindowFn, and that has its input and output types bound. Does not modify this transform. The resulting PTransform is sufficiently specified to be applied, but more properties can still be specified.

triggering

@Experimental(value=TRIGGER)
public <T> Window.Bound<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.

Must also specify allowed lateness using withAllowedLateness(org.joda.time.Duration) and accumulation mode using either discardingFiredPanes() or accumulatingFiredPanes().

discardingFiredPanes

@Experimental(value=TRIGGER)
public <T> Window.Bound<T> discardingFiredPanes()

Returns a new Window PTransform that uses the registered WindowFn and Triggering behavior, and that discards elements in a pane after they are triggered.

Does not modify this transform. The resulting PTransform is sufficiently specified to be applied, but more properties can still be specified.

accumulatingFiredPanes

@Experimental(value=TRIGGER)
public <T> Window.Bound<T> accumulatingFiredPanes()

Returns a new Window PTransform that uses the registered WindowFn and Triggering behavior, and that accumulates elements in a pane after they are triggered.

Does not modify this transform. The resulting PTransform is sufficiently specified to be applied, but more properties can still be specified.

withAllowedLateness

@Experimental(value=TRIGGER)
public <T> Window.Bound<T> withAllowedLateness(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.

Depending on the trigger this may not produce a pane with PaneInfo.isLast. See Window.ClosingBehavior.FIRE_IF_NON_EMPTY for more details.

withAllowedLateness

@Experimental(value=TRIGGER)
public <T> Window.Bound<T> withAllowedLateness(Duration allowedLateness,
                                                                            Window.ClosingBehavior behavior)

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.