code: private void determineChannelAccessor() throws ChannelFrameworkException, ChannelFactoryException {
          // Extract the factory class from the application side channel definition.
          OutboundChannelDefinition first = this.outboundChannelDefs.getFirst();
          Class<?> factoryClass = first.getOutboundFactory();
          if (factoryClass == null) {
              throw new ChannelFrameworkException("No factory class associated with outbound channel " + first);
          }
          // Get an instance of the channel factory from the framework.
          ChannelFactory outboundFactory = framework.getChannelFactoryInternal(factoryClass, false);
          if (outboundFactory == null) {
              throw new ChannelFrameworkException("No channel factory could be found for factory class " + factoryClass);
          }
          // Get the channel accessor from the factory instance.
          this.channelAccessor = outboundFactory.getApplicationInterface();
      }
docs: Identify the channel accessor class based on the application side outbound
  channel definition array.
  
  @throws ChannelFrameworkException
  @throws ChannelFactoryException