org.apache.beam.sdk.transforms.windowing

Class PaneInfo

java.lang.Object

org.apache.beam.sdk.transforms.windowing.PaneInfo

public final class PaneInfo
extends java.lang.Object

Provides information about the pane an element belongs to. Every pane is implicitly associated with a window. Panes are observable only via the DoFn.ProcessContext#pane method of the context passed to a DoFn.ProcessElement method.

Note: This does not uniquely identify a pane, and should not be used for comparisons.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	PaneInfo.PaneInfoCoder A Coder for encoding PaneInfo instances.
static class	PaneInfo.Timing Enumerates the possibilities for the timing of this pane firing related to the input and output watermarks for its computation.

Field Summary

Fields

Modifier and Type	Field and Description
static PaneInfo	NO_FIRING PaneInfo to use for elements on (and before) initial window assignment (including elements read from sources) before they have passed through a GroupByKey and are associated with a particular trigger firing.
static PaneInfo	ON_TIME_AND_ONLY_FIRING PaneInfo to use when there will be exactly one firing and it is on time.

Method Summary

Modifier and Type	Method and Description
static PaneInfo	createPane(boolean isFirst, boolean isLast, PaneInfo.Timing timing)
static PaneInfo	createPane(boolean isFirst, boolean isLast, PaneInfo.Timing timing, long index, long onTimeIndex) Factory method to create a PaneInfo with the specified parameters.
static PaneInfo	decodePane(byte encodedPane)
boolean	equals(java.lang.Object obj)
long	getIndex() The zero-based index of this trigger firing that produced this pane.
long	getNonSpeculativeIndex() The zero-based index of this trigger firing among non-speculative panes.
PaneInfo.Timing	getTiming() Return the timing of this pane.
int	hashCode()
boolean	isFirst() Return true if this is the first pane produced for the associated window.
boolean	isLast() Return true if this is the last pane that will be produced in the associated window.
boolean	isUnknown() Return true if there is no timing information for the current PaneInfo.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

NO_FIRING

public static final PaneInfo NO_FIRING

PaneInfo to use for elements on (and before) initial window assignment (including elements read from sources) before they have passed through a GroupByKey and are associated with a particular trigger firing.

ON_TIME_AND_ONLY_FIRING

public static final PaneInfo ON_TIME_AND_ONLY_FIRING

PaneInfo to use when there will be exactly one firing and it is on time.

Method Detail

createPane

public static PaneInfo createPane(boolean isFirst,
                                  boolean isLast,
                                  PaneInfo.Timing timing)

createPane

public static PaneInfo createPane(boolean isFirst,
                                  boolean isLast,
                                  PaneInfo.Timing timing,
                                  long index,
                                  long onTimeIndex)

Factory method to create a PaneInfo with the specified parameters.

decodePane

public static PaneInfo decodePane(byte encodedPane)

isUnknown

public boolean isUnknown()

Return true if there is no timing information for the current PaneInfo. This typically indicates that the current element has not been assigned to windows or passed through an operation that executes triggers yet.

isFirst

public boolean isFirst()

Return true if this is the first pane produced for the associated window.

isLast

public boolean isLast()

Return true if this is the last pane that will be produced in the associated window.

getTiming

public PaneInfo.Timing getTiming()

Return the timing of this pane.

getIndex

public long getIndex()

The zero-based index of this trigger firing that produced this pane.

This will return 0 for the first time the timer fires, 1 for the next time, etc.

A given (key, window, pane-index) is guaranteed to be unique in the output of a group-by-key operation.

getNonSpeculativeIndex

public long getNonSpeculativeIndex()

The zero-based index of this trigger firing among non-speculative panes.

This will return 0 for the first non-PaneInfo.Timing.EARLY timer firing, 1 for the next one, etc.

Always -1 for speculative data.

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object