Netty（7-2）传List

ObjectEchoServer

protected void initChannel(SocketChannel ch) throws Exception {
                    ChannelPipeline p = ch.pipeline();
                    p.addLast(new ObjectEncoder());
                    p.addLast(new ObjectDecoder(ClassResolvers.cacheDisabled(null)));
                    p.addLast(new ObjectEchoServerHandler());
                }

ObjectEchoServerHandler

public class ObjectEchoServerHandler extends ChannelInboundHandlerAdapter {

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        ctx.write(msg);
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        ctx.flush();
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        cause.printStackTrace();
        ctx.close();
    }

}

ObjectEchoClient

protected void initChannel(SocketChannel ch) throws Exception {
                    ChannelPipeline p = ch.pipeline();
                    p.addLast(new ObjectEncoder());
                    p.addLast(new ObjectDecoder(ClassResolvers.cacheDisabled(null)));
                    p.addLast(new ObjectEchoClientHandler());
                }

ObjectEchoClientHandler

public class ObjectEchoClientHandler extends ChannelInboundHandlerAdapter {
    private final List<Integer> firstMessage;

    public ObjectEchoClientHandler() {//每个channel（connection）都会new该handler
        firstMessage = new ArrayList<Integer>(ObjectEchoClient.SIZE);
        for (int i = 0; i < ObjectEchoClient.SIZE; i++) {
            firstMessage.add(Integer.valueOf(i));
        }
    }

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

    @Override
    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
        //Echo back the received object to the server.
        ctx.write(msg);
    }

    @Override
    public void channelReadComplete(ChannelHandlerContext ctx) throws Exception {
        ctx.flush();
    }

    @Override
    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
        cause.printStackTrace();
        ctx.close();
    }

}