code: public void setChannelOptions(final Map<ChannelOption, Object> channelOptions) {
          this.channelOptions = channelOptions == null ? Collections.<ChannelOption, Object> emptyMap() : channelOptions;
      }
docs: Add Netty {@link io.netty.channel.ChannelOption}s to the {@link io.netty.bootstrap.ServerBootstrap}.
  
  @param channelOptions the additional {@link io.netty.channel.ChannelOption}s.
  @see io.netty.bootstrap.ServerBootstrap#option(io.netty.channel.ChannelOption, Object)