com.espertech.esper.epl.named
Class NamedWindowConsumerView

java.lang.Object
  extended by com.espertech.esper.view.ViewSupport
      extended by com.espertech.esper.epl.named.NamedWindowConsumerView
All Implemented Interfaces:
EventCollection, StatementStopCallback, View, Viewable, Iterable<EventBean>

public class NamedWindowConsumerView
extends ViewSupport
implements StatementStopCallback

Represents a consumer of a named window that selects from a named window via a from-clause.

The view simply dispatches directly to child views, and keeps the last new event for iteration.


Field Summary
 
Fields inherited from class com.espertech.esper.view.ViewSupport
parent
 
Constructor Summary
NamedWindowConsumerView(List<ExprNode> filterList, EventType eventType, StatementStopService statementStopService, NamedWindowTailView tailView)
          Ctor.
 
Method Summary
 EventType getEventType()
          Provides metadata information about the type of object the event collection contains.
 Iterator<EventBean> iterator()
          Allows iteration through all elements in this event collection.
 void statementStopped()
          Indicates statement stopped.
 void update(EventBean[] newData, EventBean[] oldData)
          Notify that data has been added or removed from the Viewable parent.
 
Methods inherited from class com.espertech.esper.view.ViewSupport
addView, dumpChildViews, dumpUpdateParams, dumpUpdateParams, findDescendent, getParent, getViews, hasViews, removeView, setParent, updateChildren, updateChildren
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

NamedWindowConsumerView

public NamedWindowConsumerView(List<ExprNode> filterList,
                               EventType eventType,
                               StatementStopService statementStopService,
                               NamedWindowTailView tailView)
Ctor.

Parameters:
eventType - the event type of the named window
statementStopService - for registering a callback when the view stopped, to unregister the statement as a consumer
tailView - to indicate when the consumer stopped to remove the consumer
filterList - is a list of filter expressions
Method Detail

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

getEventType

public EventType getEventType()
Description copied from interface: EventCollection
Provides metadata information about the type of object the event collection contains.

Specified by:
getEventType in interface EventCollection
Returns:
metadata for the objects in the collection

iterator

public Iterator<EventBean> iterator()
Description copied from interface: EventCollection
Allows iteration through all elements in this event collection. 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 EventCollection
Specified by:
iterator in interface Iterable<EventBean>
Returns:
an iterator which will go through all current elements in the collection.

statementStopped

public void statementStopped()
Description copied from interface: StatementStopCallback
Indicates statement stopped.

Specified by:
statementStopped in interface StatementStopCallback

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