@Override
    public CompletableFuture<List<T>> collect(EventExecutor executor, SubscriptionOption... options) {
        @SuppressWarnings("unchecked")
        final StreamMessage<T> delegate = (StreamMessage<T>) delegate();
        return delegate.collect(executor, options);
    }
Returns the {@link StreamMessage} being decorated.
core/src/main/java/com/linecorp/armeria/common/stream/StreamMessageWrapper.java