com.espertech.esper.view.stat
Class WeightedAverageViewFactory

java.lang.Object
  com.espertech.esper.view.stat.WeightedAverageViewFactory

All Implemented Interfaces:

ViewFactory

public class WeightedAverageViewFactory
extends java.lang.Object
implements ViewFactory

Factory for WeightedAverageView instances.

Field Summary

protected StatViewAdditionalProps	additionalProps
protected EventType	eventType
protected ExprNode	fieldNameWeight Expression of weight field.
protected ExprNode	fieldNameX Expression of X field.
protected static java.lang.String	NAME

Constructor Summary

WeightedAverageViewFactory()

Method Summary

void	attach(EventType parentEventType, StatementContext statementContext, ViewFactory optionalParentFactory, java.util.List<ViewFactory> parentViewFactories) Attaches the factory to a parent event type such that the factory can validate attach requirements and determine an event type for resulting views.
boolean	canReuse(View view) Determines if the given view could be used instead of creating a new view, requires the view factory to compare view type, parameters and other capabilities provided.
StatViewAdditionalProps	getAdditionalProps()
EventType	getEventType() Returns the event type that the view that is created by the view factory would create for events posted by the view.
java.lang.String	getViewName() Returns the name of the view, not namespace+name but readable name.
View	makeView(AgentInstanceViewFactoryChainContext agentInstanceViewFactoryContext) Create a new view.
void	setAdditionalProps(StatViewAdditionalProps additionalProps)
void	setEventType(EventType eventType)
void	setFieldNameWeight(ExprNode fieldNameWeight)
void	setFieldNameX(ExprNode fieldNameX)
void	setViewParameters(ViewFactoryContext viewFactoryContext, java.util.List<ExprNode> expressionParameters) Indicates user EPL query view parameters to the view factory.

Methods inherited from class java.lang.Object

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

Field Detail

NAME

protected static final java.lang.String NAME

See Also:

Constant Field Values

fieldNameX

protected ExprNode fieldNameX

Expression of X field.

fieldNameWeight

protected ExprNode fieldNameWeight

Expression of weight field.

additionalProps

protected StatViewAdditionalProps additionalProps

eventType

protected EventType eventType

Constructor Detail

WeightedAverageViewFactory

public WeightedAverageViewFactory()

Method Detail

setViewParameters

public void setViewParameters(ViewFactoryContext viewFactoryContext,
                              java.util.List<ExprNode> expressionParameters)
                       throws ViewParameterException

Description copied from interface: ViewFactory

Indicates user EPL query view parameters to the view factory.

Specified by:

setViewParameters in interface ViewFactory

Parameters:

viewFactoryContext - supplied context information for the view factory

expressionParameters - is the objects representing the view parameters

Throws:

ViewParameterException - if the parameters don't match view parameter needs

attach

public void attach(EventType parentEventType,
                   StatementContext statementContext,
                   ViewFactory optionalParentFactory,
                   java.util.List<ViewFactory> parentViewFactories)
            throws ViewParameterException

Description copied from interface: ViewFactory

Attaches the factory to a parent event type such that the factory can validate attach requirements and determine an event type for resulting views.

Specified by:

attach in interface ViewFactory

Parameters:

parentEventType - is the parent event stream's or view factory's event type

statementContext - contains the services needed for creating a new event type

optionalParentFactory - is null when there is no parent view factory, or contains the parent view factory

parentViewFactories - is a list of all the parent view factories or empty list if there are none

Throws:

ViewParameterException - is thrown to indicate that this view factories's view would not play with the parent view factories view

makeView

public View makeView(AgentInstanceViewFactoryChainContext agentInstanceViewFactoryContext)

Description copied from interface: ViewFactory

Create a new view.

Specified by:

makeView in interface ViewFactory

getEventType

public EventType getEventType()

Description copied from interface: ViewFactory

Returns the event type that the view that is created by the view factory would create for events posted by the view.

Specified by:

getEventType in interface ViewFactory

Returns:

event type of view's created by the view factory

canReuse

public boolean canReuse(View view)

Description copied from interface: ViewFactory

Determines if the given view could be used instead of creating a new view, requires the view factory to compare view type, parameters and other capabilities provided.

Specified by:

canReuse in interface ViewFactory

Parameters:

view - is the candidate view to compare to

Returns:

true if the given view can be reused instead of creating a new view, or false to indicate the view is not right for reuse

getViewName

public java.lang.String getViewName()

Description copied from interface: ViewFactory

Returns the name of the view, not namespace+name but readable name.

Specified by:

getViewName in interface ViewFactory

Returns:

readable name

setFieldNameX

public void setFieldNameX(ExprNode fieldNameX)

setFieldNameWeight

public void setFieldNameWeight(ExprNode fieldNameWeight)

setAdditionalProps

public void setAdditionalProps(StatViewAdditionalProps additionalProps)

getAdditionalProps

public StatViewAdditionalProps getAdditionalProps()

setEventType

public void setEventType(EventType eventType)