|Caching Data with GemFire XD / Handling DML Events Asynchronously|
An AsyncEventListener instance is serviced by its own dedicated thread in which a callback method is invoked. Events that correspond to DML operations are placed in an internal queue, and the dedicated thread dispatches a batch of events at a time to the user-implemented callback class. The frequency of dispatching events is governed by the configuration of the AsyncEventListener in GemFire XD.
To receive DML callbacks, you create a class that implements the AsyncEventListener interface.
|Type of Event||Object of EVENT.Type enumeration. This can be AFTER_INSERT, AFTER_UPDATE, AFTER_DELETE, BEFORE_DELETE, BEFORE_INSERT, BEFORE_UPDATE, BULK_DML, or BULK_INSERT depending upon the type of CRUD operation.|
|Schema and Table Name||The schema and table name for the current operation.|
|Old Row||A result set of column values representing the old row that is being updated.|
|New Row||A result set of column values representing the new rows that are being inserted or updated.|
|Table MetaData||Information about the type, properties, and positions of the columns being returned.|
|Primary Key||A result set representing the primary key columns of the changed rows.|