in hugegraph-common/src/main/java/org/apache/hugegraph/event/EventHub.java [136:169]
public Future<Integer> notify(String event, @Nullable Object... args) {
@SuppressWarnings("resource")
ExtendableIterator<EventListener> all = new ExtendableIterator<>();
List<EventListener> ls = this.listeners.get(event);
if (ls != null && !ls.isEmpty()) {
all.extend(ls.iterator());
}
List<EventListener> lsAny = this.listeners.get(ANY_EVENT);
if (lsAny != null && !lsAny.isEmpty()) {
all.extend(lsAny.iterator());
}
if (!all.hasNext()) {
return CompletableFuture.completedFuture(0);
}
Event ev = new Event(this, event, args);
// The submit will catch params: `all`(Listeners) and `ev`(Event)
return executor().submit(() -> {
int count = 0;
// Notify all listeners, and ignore the results
while (all.hasNext()) {
try {
all.next().event(ev);
count++;
} catch (Throwable e) {
LOG.warn("Failed to handle event: {}", ev, e);
}
}
return count;
});
}