@Override
protected List<? extends HandlerMethodReturnValueHandler> initReturnValueHandlers() {
	List<HandlerMethodReturnValueHandler> handlers = new ArrayList<>();

	// Single-purpose return value types

	handlers.add(new ListenableFutureReturnValueHandler());
	handlers.add(new CompletableFutureReturnValueHandler());
	handlers.add(new ReactiveReturnValueHandler());

	// Annotation-based return value types

	SendToMethodReturnValueHandler sendToHandler =
			new SendToMethodReturnValueHandler(this.brokerTemplate, true);
	sendToHandler.setHeaderInitializer(this.headerInitializer);
	handlers.add(sendToHandler);

	SubscriptionMethodReturnValueHandler subscriptionHandler =
			new SubscriptionMethodReturnValueHandler(this.clientMessagingTemplate);
	subscriptionHandler.setHeaderInitializer(this.headerInitializer);
	handlers.add(subscriptionHandler);

	// Custom return value types

	handlers.addAll(getCustomReturnValueHandlers());

	// Catch-all

	sendToHandler = new SendToMethodReturnValueHandler(this.brokerTemplate, false);
	sendToHandler.setHeaderInitializer(this.headerInitializer);
	handlers.add(sendToHandler);

	return handlers;
}
 

@Override
protected List<? extends HandlerMethodReturnValueHandler> initReturnValueHandlers() {
	List<HandlerMethodReturnValueHandler> handlers = new ArrayList<>();

	// Single-purpose return value types

	handlers.add(new ListenableFutureReturnValueHandler());
	handlers.add(new CompletableFutureReturnValueHandler());
	handlers.add(new ReactiveReturnValueHandler());

	// Annotation-based return value types

	SendToMethodReturnValueHandler sendToHandler =
			new SendToMethodReturnValueHandler(this.brokerTemplate, true);
	sendToHandler.setHeaderInitializer(this.headerInitializer);
	handlers.add(sendToHandler);

	SubscriptionMethodReturnValueHandler subscriptionHandler =
			new SubscriptionMethodReturnValueHandler(this.clientMessagingTemplate);
	subscriptionHandler.setHeaderInitializer(this.headerInitializer);
	handlers.add(subscriptionHandler);

	// Custom return value types

	handlers.addAll(getCustomReturnValueHandlers());

	// Catch-all

	sendToHandler = new SendToMethodReturnValueHandler(this.brokerTemplate, false);
	sendToHandler.setHeaderInitializer(this.headerInitializer);
	handlers.add(sendToHandler);

	return handlers;
}
 

@Override
protected List<? extends HandlerMethodReturnValueHandler> initReturnValueHandlers() {
	List<HandlerMethodReturnValueHandler> handlers = new ArrayList<HandlerMethodReturnValueHandler>();

	// Single-purpose return value types
	handlers.add(new ListenableFutureReturnValueHandler());
	if (completableFuturePresent) {
		handlers.add(new CompletableFutureReturnValueHandler());
	}

	// Annotation-based return value types
	SendToMethodReturnValueHandler sth =
			new SendToMethodReturnValueHandler(this.brokerTemplate, true);
	sth.setHeaderInitializer(this.headerInitializer);
	handlers.add(sth);

	SubscriptionMethodReturnValueHandler sh =
			new SubscriptionMethodReturnValueHandler(this.clientMessagingTemplate);
	sh.setHeaderInitializer(this.headerInitializer);
	handlers.add(sh);

	// custom return value types
	handlers.addAll(getCustomReturnValueHandlers());

	// catch-all
	sth = new SendToMethodReturnValueHandler(this.brokerTemplate, false);
	sth.setHeaderInitializer(this.headerInitializer);
	handlers.add(sth);

	return handlers;
}