@Override
    protected void handleMessageInternal(Message<?> message) {
        RingBufferProcessor<Object> reactiveProcessorToUse = getReactiveProcessor(message);
        invokeProcessor(message, reactiveProcessorToUse);
    }
Construct a new MessageHandler given the reactor based Processor to delegate
processing to and a partition expression.

@param processor The stream based reactor processor
spring-xd-reactor/src/main/java/org/springframework/xd/reactor/MultipleBroadcasterMessageHandler.java