Floodlight 处理交换机加入/移除过程

     Floodlight 使用的是Netty架构，在Controller.java 入口函数中显示创建ServerBootstrap，设置套接字选项，ChannelPipeline，此时监听套接字就准备好处理来自SW的各种消息；这里最核心的就是 OpenflowPipelineFactory ，会加入各个业务相关的Handler，代码如下：

  public  ChannelPipeline getPipeline()  throws  Exception {

        OFChannelState state =  new  OFChannelState();

       

        ChannelPipeline pipeline = Channels. pipeline();

        pipeline.addLast(  "ofmessagedecoder" ,  new  OFMessageDecoder());

        pipeline.addLast(  "ofmessageencoder" ,  new  OFMessageEncoder());

        pipeline.addLast(  "idle" ,  idleHandler  );

        pipeline.addLast(  "timeout" ,  readTimeoutHandler  );

        pipeline.addLast(  "handshaketimeout" ,

                          new  HandshakeTimeoutHandler(state,  timer  , 15));

         if  ( pipelineExecutor  !=  null )

            pipeline.addLast(</