VMware Tanzu GemFire .NET Client API Reference

VMware Tanzu GemFire .NET Client: ICqListener< TKey, TResult > Interface Template Reference
VMware Tanzu GemFire .NET Client
Public Member Functions | List of all members
ICqListener< TKey, TResult > Interface Template Reference

An application plug-in that can be installed on a region. Continuous Query Listener change notifications are invoked after the change has occured. More...

Public Member Functions

void OnEvent (ICqEvent< TKey, TResult > ev)
 Handles all ICqEvent<TKey, TResult> events generated by a Continuous Query More...
 
void OnError (ICqEvent< TKey, TResult > ev)
 Handles the errors generated by a Continuous Query More...
 
void Close ()
 Called when the region containing this callback is destroyed, when the cache is closed. More...
 

Detailed Description

An application plug-in that can be installed on a region. Continuous Query Listener change notifications are invoked after the change has occured.

Listeners receive notifications when entries in a region change and satisfy the query.

A CQ listener set using ICqAttributesFactory<TKey, TResult>.AddCqListener(GemFire.Client.ICqListener<TKey, TResult>).

The methods on a ICQListener are invoked asynchronously. Multiple events can cause concurrent invocation of ICQListener methods. If event A occurs before event B, there is no guarantee that their corresponding ICQListener method invocations will occur in the same order. Any exceptions thrown by the listener are caught by GemFire and logged.

CQListeners are user callbacks that are invoked by GemFire. It is important to ensure that minimal work is done in the listener before returning control back to GemFire. For example, a listener implementation may choose to hand off the event to a thread pool that then processes the event on its thread rather than the listener thread

Member Function Documentation

◆ Close()

void ICqListener< TKey, TResult >.Close ( )

Called when the region containing this callback is destroyed, when the cache is closed.

Implementations should clean up 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.

◆ OnError()

void ICqListener< TKey, TResult >.OnError ( ICqEvent< TKey, TResult >  ev)

Handles the errors generated by a Continuous Query

◆ OnEvent()

void ICqListener< TKey, TResult >.OnEvent ( ICqEvent< TKey, TResult >  ev)

Handles all ICqEvent<TKey, TResult> events generated by a Continuous Query

The documentation for this interface was generated from the following file:
  • gemfire.client/Interfaces/ICqListener.cs