程序包 org.apache.pulsar.functions.windowing

类 WindowManager<T>

java.lang.Object

org.apache.pulsar.functions.windowing.WindowManager<T>

类型参数:

T - the type of event in the window.

所有已实现的接口:

TriggerHandler

public class WindowManager<T>
extends Object
implements TriggerHandler

Tracks a window of events and fires WindowLifecycleListener callbacks on expiry of events or activation of the window due to TriggerPolicy.

字段概要

字段

修饰符和类型	字段	说明
protected EvictionPolicy<T,?>	evictionPolicy
protected static final int	EXPIRE_EVENTS_THRESHOLD	Expire old events every EXPIRE_EVENTS_THRESHOLD to keep the window size in check.
protected final Collection<Event<T>>	queue
protected TriggerPolicy<T,?>	triggerPolicy
protected final WindowLifecycleListener<Event<T>>	windowLifecycleListener

构造器概要

构造器

构造器	说明
WindowManager(WindowLifecycleListener<Event<T>> lifecycleListener, Collection<Event<T>> queue)	Constructs a WindowManager

方法概要

修饰符和类型	方法	说明
void	add(Event<T> windowEvent)	Tracks a window event
void	add(T event, long ts, org.apache.pulsar.functions.api.Record<?> record)	Add an event into the window, with the given ts as the tracking ts.
protected void	compactWindow()	expires events that fall out of the window every EXPIRE_EVENTS_THRESHOLD so that the window does not grow too big.
long	getEarliestEventTs(long startTs, long endTs)	Scans the event queue and returns the next earliest event ts between the startTs and endTs.
int	getEventCount(long referenceTime)	Scans the event queue and returns number of events having timestamp less than or equal to the reference time.
List<Long>	getSlidingCountTimestamps(long startTs, long endTs, int slidingCount)	Scans the event queue and returns the list of event ts falling between startTs (exclusive) and endTs (inclusive) at each sliding interval counts.
boolean	onTrigger()	The callback invoked by the trigger policy.
void	setEvictionPolicy(EvictionPolicy<T,?> evictionPolicy)
void	setTriggerPolicy(TriggerPolicy<T,?> triggerPolicy)
void	shutdown()
String	toString()

从类继承的方法 java.lang.Object

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

字段详细资料

EXPIRE_EVENTS_THRESHOLD

protected static final int EXPIRE_EVENTS_THRESHOLD

Expire old events every EXPIRE_EVENTS_THRESHOLD to keep the window size in check.

Note that if the eviction policy is based on watermarks, events will not be evicted until a new watermark would cause them to be considered expired anyway, regardless of this limit

另请参阅:

• 常量字段值

queue

protected final Collection<Event<T>> queue

evictionPolicy

protected EvictionPolicy<T,?> evictionPolicy

triggerPolicy

protected TriggerPolicy<T,?> triggerPolicy

windowLifecycleListener

protected final WindowLifecycleListener<Event<T>> windowLifecycleListener

构造器详细资料

WindowManager

public WindowManager(WindowLifecycleListener<Event<T>> lifecycleListener,
 Collection<Event<T>> queue)

Constructs a WindowManager

参数:

lifecycleListener - the WindowLifecycleListener

queue - a collection where the events in the window can be enqueued.
Note: This collection has to be thread safe.

方法详细资料

setEvictionPolicy

public void setEvictionPolicy(EvictionPolicy<T,?> evictionPolicy)

setTriggerPolicy

public void setTriggerPolicy(TriggerPolicy<T,?> triggerPolicy)

add

public void add(T event,
 long ts,
 org.apache.pulsar.functions.api.Record<?> record)

Add an event into the window, with the given ts as the tracking ts.

参数:

event - the event to track

ts - the timestamp

add

public void add(Event<T> windowEvent)

Tracks a window event

参数:

windowEvent - the window event to track

onTrigger

public boolean onTrigger()

The callback invoked by the trigger policy.

指定者:

onTrigger 在接口中 TriggerHandler

返回:

true if the window was evaluated with at least one event in the window, false otherwise

shutdown

public void shutdown()

compactWindow

protected void compactWindow()

expires events that fall out of the window every EXPIRE_EVENTS_THRESHOLD so that the window does not grow too big.

getEarliestEventTs

public long getEarliestEventTs(long startTs,
 long endTs)

Scans the event queue and returns the next earliest event ts between the startTs and endTs.

参数:

startTs - the start ts (exclusive)

endTs - the end ts (inclusive)

返回:

the earliest event ts between startTs and endTs

getEventCount

public int getEventCount(long referenceTime)

Scans the event queue and returns number of events having timestamp less than or equal to the reference time.

参数:

referenceTime - the reference timestamp in millis

返回:

the count of events with timestamp less than or equal to referenceTime

getSlidingCountTimestamps

public List<Long> getSlidingCountTimestamps(long startTs,
 long endTs,
 int slidingCount)

Scans the event queue and returns the list of event ts falling between startTs (exclusive) and endTs (inclusive) at each sliding interval counts.

参数:

startTs - the start timestamp (exclusive)

endTs - the end timestamp (inclusive)

slidingCount - the sliding interval count

返回:

the list of event ts

toString

public String toString()

覆盖:

toString 在类中 Object