com.espertech.esper.client.hook
Interface VirtualDataWindowFactory

public interface VirtualDataWindowFactory

Factory for VirtualDataWindow.

Register an implementation of this interface with the engine before use: configuration.addPlugInVirtualDataWindow("test", "vdw", SupportVirtualDWFactory.class.getName());

Method Summary

VirtualDataWindow	create(VirtualDataWindowContext context) Invoked for each context partition (or once if not using contexts), return a virtual data window to handle the specific event type, named window or paramaters as provided in the context.
void	destroyAllContextPartitions() Invoked to indicate the named window is destroyed.
java.util.Set<java.lang.String>	getUniqueKeyPropertyNames() Return the names of properties that taken together (combined, composed, not individually) are the unique keys of a row, return null if there are no unique keys that can be identified.
void	initialize(VirtualDataWindowFactoryContext factoryContext) Invoked once after instantiation of the factory, exactly once per named window.

Method Detail

initialize

void initialize(VirtualDataWindowFactoryContext factoryContext)

Invoked once after instantiation of the factory, exactly once per named window.

Parameters:

factoryContext - factory context provides contextual information such as event type, named window name and parameters.

create

VirtualDataWindow create(VirtualDataWindowContext context)

Invoked for each context partition (or once if not using contexts), return a virtual data window to handle the specific event type, named window or paramaters as provided in the context.

This method is invoked for each named window instance after the initialize method. If using context partitions, the method is invoked once per context partition per named window.

Parameters:

context - provides contextual information such as event type, named window name and parameters and including context partition information

Returns:

virtual data window

destroyAllContextPartitions

void destroyAllContextPartitions()

Invoked to indicate the named window is destroyed.

This method is invoked once per named window (and not once per context partition).

For reference, the VirtualDataWindow destroy method is called once per context partition, before this method is invoked.

getUniqueKeyPropertyNames

java.util.Set<java.lang.String> getUniqueKeyPropertyNames()

Return the names of properties that taken together (combined, composed, not individually) are the unique keys of a row, return null if there are no unique keys that can be identified.

Returns:

set of unique key property names