Being notified about data changes can be rather useful as we can make an application-level decision regarding whether the change is important or not and react accordingly. The first interface that we are going to look at is EntryListener
. This class will notify us when changes are made to the entries stored in a map collection. If we take a look at the interface, we can see four entry event types and two map-wide events that we will be notified about. EntryListener
has also being broken up into a number of individual super MapListener
interfaces. So, should we be interested in only a subset of event types, we can implement the appropriate super interfaces as required. Let's take a look at the following code:
void entryAdded(EntryEvent<K, V> event); void entryRemoved(EntryEvent<K, V> event); void entryUpdated(EntryEvent<K, V> event); void entryEvicted(EntryEvent<K, V> event); void mapCleared(MapEvent event); void mapEvicted(MapEvent event)...