VMware GemFire Java API Reference

public interface AsyncEventListener
extends CacheCallback

A callback for events passing through the AsyncEventQueue to which this listener is attached. Implementers of interface AsyncEventListener process batches of AsyncEvent delivered by the corresponding AsyncEventQueue.
A sample implementation of this interface is as follows:

 public class MyEventListener implements AsyncEventListener {

   public boolean processEvents(List<AsyncEvent> events) {
     for (Iterator i = events.iterator(); i.hasNext();) {
       AsyncEvent event = (AsyncEvent) i.next();

       String originalRegionName = event.getRegion().getName();
       // For illustration purpose, use the event to update the duplicate of above region.
       final Region duplicateRegion =
           CacheHelper.getCache().getRegion(originalRegionName + "_DUP");

       final Object key = event.getKey();
       final Object value = event.getDeserializedValue();
       final Operation op = event.getOperation();

       if (op.isCreate()) {
         duplicateRegion.create(key, value);
       } else if (op.isUpdate()) {
         duplicateRegion.put(key, value);
       } else if (op.isDestroy()) {
         duplicateRegion.destroy(key);
       }

     }
     return true;
   }
 }