net.esper.eql.named
Class NamedWindowRootView

java.lang.Object
  extended by net.esper.view.ViewSupport
      extended by net.esper.eql.named.NamedWindowRootView
All Implemented Interfaces:
Iterable<EventBean>, EventCollection, View, Viewable

public class NamedWindowRootView
extends ViewSupport

The root window in a named window plays multiple roles: It holds the indexes for deleting rows, if any on-delete statement requires such indexes. Such indexes are updated when events arrive, or remove from when a data window or on-delete statement expires events. The view keeps track of on-delete statements their indexes used.


Field Summary
 
Fields inherited from class net.esper.view.ViewSupport
parent
 
Constructor Summary
NamedWindowRootView()
          Ctor.
 
Method Summary
 NamedWindowOnExprBaseView addOnExpr(OnTriggerDesc onTriggerDesc, ExprNode joinExpr, EventType filterEventType, StatementStopService statementStopService, InternalEventRouter internalEventRouter, ResultSetProcessor optionalResultSetProcessor, EPStatementHandle statementHandle)
          Add an on-trigger view that, using a lookup strategy, looks up from the named window and may select or delete rows.
 void destroy()
          Destroy and clear resources.
 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 removeOldData(EventBean[] oldData)
          Called by tail view to indicate that the data window view exired events that must be removed from index tables.
 void removeOnExpr(LookupStrategy strategy)
          Unregister an on-delete statement view, using the strategy as a key to remove a reference to the index table used by the strategy.
 void setDataWindowContents(Iterable<EventBean> dataWindowContents)
          Sets the iterator to use to obtain current named window data window contents.
 void setParent(Viewable parent)
          Called when the View is added to a Viewable object.
 void update(EventBean[] newData, EventBean[] oldData)
          Notify that data has been added or removed from the Viewable parent.
 
Methods inherited from class net.esper.view.ViewSupport
addView, dumpChildViews, dumpUpdateParams, findDescendent, getParent, getViews, hasViews, removeView, updateChildren, updateChildren
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

NamedWindowRootView

public NamedWindowRootView()
Ctor.

Method Detail

setDataWindowContents

public void setDataWindowContents(Iterable<EventBean> dataWindowContents)
Sets the iterator to use to obtain current named window data window contents.

Parameters:
dataWindowContents - iterator over events help by named window

removeOldData

public void removeOldData(EventBean[] oldData)
Called by tail view to indicate that the data window view exired events that must be removed from index tables.

Parameters:
oldData - removed stream of the data window

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.

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

addOnExpr

public NamedWindowOnExprBaseView addOnExpr(OnTriggerDesc onTriggerDesc,
                                           ExprNode joinExpr,
                                           EventType filterEventType,
                                           StatementStopService statementStopService,
                                           InternalEventRouter internalEventRouter,
                                           ResultSetProcessor optionalResultSetProcessor,
                                           EPStatementHandle statementHandle)
Add an on-trigger view that, using a lookup strategy, looks up from the named window and may select or delete rows.

Parameters:
onTriggerDesc - the specification for the on-delete
filterEventType - the event type for the on-clause in the on-delete
statementStopService - for stopping the statement
internalEventRouter - for insert-into behavior
optionalResultSetProcessor - @return view representing the on-delete view chain, posting delete events to it's listeners
statementHandle - is the handle to the statement, used for routing/insert-into
joinExpr - is the join expression or null if there is none
Returns:
base view for on-trigger expression

removeOnExpr

public void removeOnExpr(LookupStrategy strategy)
Unregister an on-delete statement view, using the strategy as a key to remove a reference to the index table used by the strategy.

Parameters:
strategy - to use for deleting events

setParent

public void setParent(Viewable parent)
Description copied from interface: View
Called when the View is added to a Viewable object.

Specified by:
setParent in interface View
Overrides:
setParent in class ViewSupport
Parameters:
parent - is the parent that this view is a child of

getEventType

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

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.

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

destroy

public void destroy()
Destroy and clear resources.


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