Netty对Protocol Buffer的支持（七）

Netty对Protocol Buffer的支持（七）

一.简介

　　在上一篇博文中笔者已经介绍了google的Protocol Buffer的使用，那么本文笔者就开始介绍netty对Protocol Buffer的支持。

二.编码的实现

2.1 服务端启动代码

public class ServerTest {
    public static void main(String[] args) throws Exception {
        EventLoopGroup bossGroup = new NioEventLoopGroup();
        EventLoopGroup workerGroup = new NioEventLoopGroup();

        try{
            ServerBootstrap serverBootstrap = new ServerBootstrap();

            serverBootstrap.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class)
                           .handler(new LoggingHandler(LogLevel.INFO))
                           .childHandler(new ServerChannelInitilizer());

            ChannelFuture channelFuture = serverBootstrap.bind(8989).sync();
            channelFuture.channel().closeFuture().sync();
        }finally{
            bossGroup.shutdownGracefully();
            workerGroup.shutdownGracefully();
        }
    }
}

2.2 服务端管道初始化代码

public class ServerChannelInitilizer extends ChannelInitializer<SocketChannel>{

    @Override
    protected void initChannel(SocketChannel ch) throws Exception {
        ChannelPipeline pipeline = ch.pipeline();

        /**
         * 采用Base 128 Varints进行编码，在消息头上加上32个整数，来标注数据的长度。
         */
        pipeline.addLast("protobufVarint32FrameDecoder", new ProtobufVarint32FrameDecoder());
        pipeline.addLast("protobufDecoder", new ProtobufDecoder(PersonsBook.AddressBook.getDefaultInstance()));

        /**
         * 对采用Base 128 Varints进行编码的数据解码
         */
        pipeline.addLast("protobufVarint32LengthFieldPrepender", new ProtobufVarint32LengthFieldPrepender());
        pipeline.addLast("protobufEncoder", new ProtobufEncoder());

        pipeline.addLast("serverHandler", new ServerHandler());
    }
}

2.3 服务端Handler处理

public class ServerHandler extends SimpleChannelInboundHandler<AddressBook>{

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, AddressBook msg) throws Exception {
        List<Person> list = msg.getPersonList();
        list.forEach(p -> System.out.println(p.getName() + ";;" + p.getId() + ";;" + p.getEmail()));
    }
}

2.4 客户端启动程序

public class ClientTest {
    public static void main(String[] args) throws Exception {
        EventLoopGroup eventLoopGroup = new NioEventLoopGroup();

        try{
            Bootstrap bootstrap = new Bootstrap();
            bootstrap.group(eventLoopGroup).channel(NioSocketChannel.class)
                     .handler(new ClientChannelInitializer());

            ChannelFuture channelFuture = bootstrap.connect("localhost", 8989).sync();
            channelFuture.channel().closeFuture().sync();
        }finally{
            eventLoopGroup.shutdownGracefully();
        }
    }
}

2.5客户端通道初始化

public class ClientChannelInitializer extends ChannelInitializer<SocketChannel>{

    @Override
    protected void initChannel(SocketChannel ch) throws Exception {
        ChannelPipeline pipeline = ch.pipeline();

        pipeline.addLast("protobufVarint32FrameDecoder", new ProtobufVarint32FrameDecoder());
        pipeline.addLast("protobufDecoder", new ProtobufDecoder(PersonsBook.AddressBook.getDefaultInstance()));
        pipeline.addLast("protobufVarint32LengthFieldPrepender", new ProtobufVarint32LengthFieldPrepender());
        pipeline.addLast("protobufEncoder", new ProtobufEncoder());

        pipeline.addLast("clientHandler", new ClientHandler());
    }
}

2.6 客户端Handler处理代码

public class ClientHandler extends SimpleChannelInboundHandler<AddressBook>{

    @Override
    protected void channelRead0(ChannelHandlerContext ctx, AddressBook msg) throws Exception {

    }

    @Override
    public void channelActive(ChannelHandlerContext ctx) throws Exception {
        AddressBook ab = AddressBook.newBuilder()
                    .addPerson(Person.newBuilder().setEmail("[e-mail]").setId(23).setName("zhangsan"))
                    .addPerson(Person.newBuilder().setEmail("[e-mail]").setId(45).setName("lisi"))
                    .build();

        ctx.writeAndFlush(ab);
    }
}

三.程序运行

　　先运行服务端启动代码，在运行客户端启动代码。