One great feature of Hazelcast is its ability to notify us of the goings-on of our persisted data and the cluster as a whole, allowing us to register an interest in events. The listener concept is borrowed from Java. So, you should feel pretty familiar with it. To provide this, there are a number of listener interfaces that we can implement to receive, process, and handle different types of events—one of which we previously encountered. The following are the listener interfaces:
Collection listeners:
EntryListeneris used for map-based (IMapandMultiMap) eventsItemListeneris used for flat collection-based (IList,ISet, andIQueue) eventsMessageListeneris used to receive topic events, but as we've seen before, it is used as a part of the standard operation of topicsQuorumListeneris used for quorum state change events
Cluster listeners: