Documentation Version: 3.5 - Publication Date : Jun 17, 2015

EntryListener on Replicated Map

A com.hazelcast.core.EntryListener used on a Replicated Map serves the same purpose as it would on other data structures in Hazelcast. You can use it to react on add, update, and remove operations. Replicated maps do not yet support eviction.

The fundamental difference in Replicated Map behavior, compared to the other data structures, is that an EntryListener only reflects changes on local data. Since replication is asynchronous, all listener events are fired only when an operation is finished on a local node. Events can fire at different times on different nodes.

import com.hazelcast.core.EntryEvent;
import com.hazelcast.core.EntryListener;
import com.hazelcast.core.Hazelcast;
import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.core.ReplicatedMap;

HazelcastInstance hazelcastInstance = Hazelcast.newHazelcastInstance();
ReplicatedMap<String, Customer> customers =
    hazelcastInstance.getReplicatedMap( "customers" );

customers.addEntryListener( new EntryListener<String, Customer>() {
  @Override
  public void entryAdded( EntryEvent<String, Customer> event ) {
    log( "Entry added: " + event );
  }

  @Override
  public void entryUpdated( EntryEvent<String, Customer> event ) {
    log( "Entry updated: " + event );
  }

  @Override
  public void entryRemoved( EntryEvent<String, Customer> event ) {
    log( "Entry removed: " + event );
  }

  @Override
  public void entryEvicted( EntryEvent<String, Customer> event ) {
    // Currently not supported, will never fire
  }
});

customers.put( "1", new Customer( "Joe", "Smith" ) ); // add event
customers.put( "1", new Customer( "Ali", "Selam" ) ); // update event
customers.remove( "1" ); // remove event