com.espertech.esper.common.internal.view.timelengthbatch

Class TimeLengthBatchView

java.lang.Object

com.espertech.esper.common.internal.view.core.ViewSupport

com.espertech.esper.common.internal.view.timelengthbatch.TimeLengthBatchView

All Implemented Interfaces:

AgentInstanceStopCallback, DataWindowView, View, Viewable, ViewDataVisitable, Iterable<EventBean>

public class TimeLengthBatchView
extends ViewSupport
implements AgentInstanceStopCallback, DataWindowView

A data view that aggregates events in a stream and releases them in one batch if either one of these conditions is reached, whichever comes first: One, a time interval passes. Two, a given number of events collected.

The view releases the batched events after the interval or number of events as new data to child views. The prior batch if not empty is released as old data to child view. The view DOES release intervals with no old or new data. It does not collect old data published by a parent view. If there are no events in the current and prior batch, the view WILL invoke the update method of child views.

The view starts the first interval when the view is created.

Field Summary

Fields

Modifier and Type	Field and Description
protected Long	callbackScheduledTime
protected ArrayList<EventBean>	currentBatch
protected EPStatementHandleCallbackSchedule	handle
protected ArrayList<EventBean>	lastBatch

Fields inherited from class com.espertech.esper.common.internal.view.core.ViewSupport

child, parent

Fields inherited from interface com.espertech.esper.common.internal.context.util.AgentInstanceStopCallback

INSTANCE_NO_ACTION

Constructor Summary

Constructors

Constructor and Description
TimeLengthBatchView(TimeLengthBatchViewFactory factory, int size, AgentInstanceViewFactoryChainContext agentInstanceContext, ViewUpdatedCollection viewUpdatedCollection, TimePeriodProvide timePeriodProvide)

Method Summary

Modifier and Type	Method and Description
EventType	getEventType() Provides metadata information about the type of object the event collection contains.
ViewFactory	getViewFactory()
void	internalHandleAdded(EventBean newEvent)
void	internalHandleRemoved(EventBean eventBean)
boolean	isEmpty() Returns true if the window is empty, or false if not empty.
Iterator<EventBean>	iterator() Allows iteration through all elements in this viewable.
protected void	scheduleCallback(long delta)
protected void	sendBatch(boolean isFromSchedule) This method updates child views and clears the batch of events.
void	stop(AgentInstanceStopServices services)
String	toString()
void	update(EventBean[] newData, EventBean[] oldData) Notify that data has been added or removed from the Viewable parent.
void	visitView(ViewDataVisitor viewDataVisitor)

Methods inherited from class com.espertech.esper.common.internal.view.core.ViewSupport

getChild, getParent, setChild, setParent

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.espertech.esper.common.internal.view.core.View

getParent, setParent

Methods inherited from interface com.espertech.esper.common.internal.view.core.Viewable

getChild, setChild

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

lastBatch

protected ArrayList<EventBean> lastBatch

currentBatch

protected ArrayList<EventBean> currentBatch

callbackScheduledTime

protected Long callbackScheduledTime

handle

protected EPStatementHandleCallbackSchedule handle

Constructor Detail

TimeLengthBatchView

public TimeLengthBatchView(TimeLengthBatchViewFactory factory,
                           int size,
                           AgentInstanceViewFactoryChainContext agentInstanceContext,
                           ViewUpdatedCollection viewUpdatedCollection,
                           TimePeriodProvide timePeriodProvide)

Method Detail

getEventType

public final EventType getEventType()

Description copied from interface: Viewable

Provides metadata information about the type of object the event collection contains.

Specified by:

getEventType in interface Viewable

Returns:

metadata for the objects in the collection

update

public void update(EventBean[] newData,
                   EventBean[] oldData)

Description copied from interface: View

Notify that data has been added or removed from the Viewable parent. The last object in the newData array of objects would be the newest object added to the parent view. The first object of the oldData array of objects would be the oldest object removed from the parent view.

If the call to update contains new (inserted) data, then the first argument will be a non-empty list and the second will be empty. Similarly, if the call is a notification of deleted data, then the first argument will be empty and the second will be non-empty. Either the newData or oldData will be non-null. This method won't be called with both arguments being null, but either one could be null. The same is true for zero-length arrays. Either newData or oldData will be non-empty. If both are non-empty, then the update is a modification notification.

When update() is called on a view by the parent object, the data in newData will be in the collection of the parent, and its data structures will be arranged to reflect that. The data in oldData will not be in the parent's data structures, and any access to the parent will indicate that that data is no longer there.

Specified by:

update in interface View

Parameters:

newData - is the new data that has been added to the parent view

oldData - is the old data that has been removed from the parent view

internalHandleAdded

public void internalHandleAdded(EventBean newEvent)

internalHandleRemoved

public void internalHandleRemoved(EventBean eventBean)

sendBatch

protected void sendBatch(boolean isFromSchedule)

This method updates child views and clears the batch of events. We cancel and old callback and schedule a new callback at this time if there were events in the batch.

Parameters:

isFromSchedule - true if invoked from a schedule, false if not

isEmpty

public boolean isEmpty()

Returns true if the window is empty, or false if not empty.

Returns:

true if empty

iterator

public final Iterator<EventBean> iterator()

Description copied from interface: Viewable

Allows iteration through all elements in this viewable. The iterator will return the elements in the collection in their natural order, or, if there is no natural ordering, in some unpredictable order.

Specified by:

iterator in interface Viewable

Specified by:

iterator in interface Iterable<EventBean>

Returns:

an iterator which will go through all current elements in the collection.

toString

public final String toString()

Overrides:

toString in class Object

scheduleCallback

protected void scheduleCallback(long delta)

stop

public void stop(AgentInstanceStopServices services)

Specified by:

stop in interface AgentInstanceStopCallback

visitView

public void visitView(ViewDataVisitor viewDataVisitor)

Specified by:

visitView in interface ViewDataVisitable

getViewFactory

public ViewFactory getViewFactory()