Apache Geode Native C++ Reference  1.14.0
apache::geode::client::CqListener Class Reference

Application plug-in interface for handling continuous query events after they occur. More...

Inherited by apache::geode::client::CqStatusListener.

Public Member Functions

virtual void close ()
 Called when the region containing this callback is closed or destroyed, when the cache is closed, or when a callback is removed from a region using an AttributesMutator. More...
 
virtual void onError (const CqEvent &aCqEvent)
 This method is invoked when there is an error during CQ processing. More...
 
virtual void onEvent (const CqEvent &aCqEvent)
 This method is invoked when an event is occurred on the region that satisfied the query condition of this CQ. More...
 

Detailed Description

Application plug-in interface for handling continuous query events after they occur.

The listener has two methods, one that is called when there is an event satisfied by the CQ and the other called when there is an error during CQ processing.

Member Function Documentation

◆ close()

virtual void apache::geode::client::CqListener::close ( )
virtual

Called when the region containing this callback is closed or destroyed, when the cache is closed, or when a callback is removed from a region using an AttributesMutator.

Implementations should cleanup any external resources such as database connections. Any runtime exceptions this method throws will be logged.

It is possible for this method to be called multiple times on a single callback instance, so implementations must be tolerant of this.

See also
Cache::close()
Region::close
Region::localDestroyRegion()
Region::destroyRegion()
AttributesMutator

◆ onError()

virtual void apache::geode::client::CqListener::onError ( const CqEvent aCqEvent)
virtual

This method is invoked when there is an error during CQ processing.

The error can appear while applying query condition on the event. e.g if the event doesn't has attributes as specified in the CQ query. This event does contain an error. The newValue may or may not be available, and will be nullptr if not available.

◆ onEvent()

virtual void apache::geode::client::CqListener::onEvent ( const CqEvent aCqEvent)
virtual

This method is invoked when an event is occurred on the region that satisfied the query condition of this CQ.

This event does not contain an error.


Apache Geode C++ Cache API Documentation