public abstract class AbstractNioByteChannel extends AbstractNioChannel 

{

    protected class NioByteUnsafe extends AbstractNIoUnsafe {

     @Override
    public final void read() {
        final ChannelPipeline pipeline = pipeline();
        ……
        // 读取结果.

        byteBuf = allocHandle.allocate(allocator);
        ……
        int localReadAmount = doReadBytes(byteBuf);
         ………

  // dispatch结果到Handler

        pipeline.fireChannelRead(byteBuf);
      ……
   }

public class ChannelInboundHandlerAdapter extends ChannelHandlerAdapter implements ChannelInboundHandler

{

//默认的通道激活操作

@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
    ctx.fireChannelActive();
}

//默认的通道读操作
@Override
public void channelRead(ChannelHandlerContext ctx,Object msg) throws Exception {
    ctx.fireChannelRead(msg);
}

}

abstract class AbstractChannelHandlerContext extends DefaultAttributeMap implements ChannelHandlerContext 

{

  volatile AbstractChannelHandlerContext next;
  volatile AbstractChannelHandlerContext prev;

@Override
public ChannelHandlerContext fireChannelRead(final Object msg) {
    invokeChannelRead(findContextInbound(),msg);
    return this;
}
static void invokeChannelRead(final AbstractChannelHandlerContext next,final Object msg) {
  ……
        next.invokeChannelRead(msg);
  ……
}

private void invokeChannelRead(Object msg) {
  ……
       ((ChannelInboundHandler) handler()).channelRead(this,msg);
    ……
}

private AbstractChannelHandlerContext findContextInbound() {
    AbstractChannelHandlerContext ctx = this;
    do {
        ctx = ctx.next;
    } while (!ctx.inbound);
    return ctx;
}

}

private AbstractChannelHandlerContext findContextOutbound() {    AbstractChannelHandlerContext ctx = this;    do {        ctx = ctx.prev;    } while (!ctx.outbound);    return ctx;}