com.espertech.esper.view.std

Class SizeView

java.lang.Object

com.espertech.esper.view.ViewSupport

com.espertech.esper.view.std.SizeView

All Implemented Interfaces:

EventCollection, View, Viewable, java.lang.Iterable<EventBean>

public class SizeView
extends ViewSupport

This view is a very simple view presenting the number of elements in a stream or view. The view computes a single long-typed count of the number of events passed through it similar to the base statistics COUNT column.

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.Object[]	lastValuesEventNew
protected long	size

Fields inherited from class com.espertech.esper.view.ViewSupport

EMPTY_VIEW_ARRAY, parent

Constructor Summary

Constructors

Constructor and Description
SizeView(AgentInstanceContext agentInstanceContext, EventType eventType, StatViewAdditionalProps additionalProps)

Method Summary

Modifier and Type	Method and Description
static EventType	createEventType(StatementContext statementContext, StatViewAdditionalProps additionalProps, int streamNum)
EventType	getEventType() Provides metadata information about the type of object the event collection contains.
java.util.Iterator<EventBean>	iterator() Allows iteration through all elements in this event collection.
java.lang.String	toString()
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, addView, dumpChildViews, dumpUpdateParams, dumpUpdateParams, findDescendent, findViewIndex, getParent, getViews, hasViews, removeAllViews, removeView, removeView, setParent, updateChildren, updateChildren

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

size

protected long size

lastValuesEventNew

protected java.lang.Object[] lastValuesEventNew

Constructor Detail

SizeView

public SizeView(AgentInstanceContext agentInstanceContext,
                EventType eventType,
                StatViewAdditionalProps additionalProps)

Method Detail

getEventType

public final 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

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

iterator

public final java.util.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.

toString

public final java.lang.String toString()

Overrides:

toString in class java.lang.Object

createEventType

public static EventType createEventType(StatementContext statementContext,
                                        StatViewAdditionalProps additionalProps,
                                        int streamNum)