![]() | UpdateListener Interface |
Also see [!:StatementAwareUpdateListener] for Update listeners that require the statement and service provider instance to be passed to the listener in addition to events.
Namespace: com.espertech.esper.runtime.client
public interface UpdateListener
The UpdateListener type exposes the following members.
Name | Description | |
---|---|---|
![]() | Update |
Notify that new events are available or old events are removed.
If the call to Update contains new (inserted) events, 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 events, then the first argument will be empty and the second will be non-empty. Either the newEvents or oldEvents will be non-null. This method won't be called with both arguments being null, (unless using output rate limiting or force-output options), but either one could be null. The same is true for zero-length arrays. Either newEvents or oldEvents will be non-empty. This method won't be called with both arguments being null (unless using output rate limiting or force-output options), but either one could be null. The same is true for zero-length arrays. Either newEvents or oldEvents will be non-empty.If both are non-empty, then the update is a modification. |