Will infinite chain of CompletableFuture be garbage collected?

I am using CompletableFuture to publish events. Since there is a requirement that the order of the events need to be maintained, I am chaining them by key using thenCompose. I am concerned about garbage collection with such an approach using infinite chaining. Will additional calls maintain references to previous CompletableFuture and not allow for them to ever be garbage collected?

Map<Integer, CompletableFuture<EventResult>> eventFutureMap = new HashMap<>();

Publisher publisher;
    
public CompletableFuture<EventResult> publish(Event event) {
    CompletableFuture<EventResult> eventFuture;
        Integer key = event.getKey();
        CompletableFuture<EventResult> existingEvent = eventFutureMap.get(key);
        if (existingEvent != null) {
            eventFuture = existingEvent.thenCompose((EventResult meta) -> publisher.publish(event));
        } else {
            eventFuture = publisher.publish(event);
        }
        eventFutureMap.put(key, eventFuture);
    return eventFuture;
}