Netty的Protobuf开发列子

1.首先创建.proto文件

package com.netty.code.protobuf;

option java_package = "com.phei.netty.protobuf";
option java_outer_classname = "SubscribeReqProto";

message SubscribeReq{

required int32 subReqID= 1;

required string userName = 2;

required string productName= 3;

repeated string address = 4;

}

package com.netty.code.protobuf;

option java_package = "com.phei.netty.protobuf";
option java_outer_classname = "SubscribeRespProto";

message SubscribeResp{

required int32 subReqID = 1;

required int32 respCode = 2;

required string desc = 3;

}

2.通过protoc.exe，生成java文件

3. 将生成的java文件拷贝到相应的包下

4.Netty服务端类

package com.phei.netty.protobuf;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.codec.DelimiterBasedFrameDecoder;
import io.netty.handler.codec.LineBasedFrameDecoder;
import io.netty.handler.codec.protobuf.ProtobufDecoder;
import io.netty.handler.codec.protobuf.ProtobufEncoder;
import io.netty.handler.codec.protobuf.ProtobufVarint32FrameDecoder;
import io.netty.handler.codec.protobuf.ProtobufVarint32LengthFieldPrepender;
import io.netty.handler.codec.string.StringDecoder;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;
/**
* 服务端
* @author renhj
*
*/
public class SubReqServer {

public void bind(int port) throws Exception{

//第一个用户服务器接收客户端的连接
EventLoopGroup bossGroup = new NioEventLoopGroup();
//第二个用户SocketChannel的网络读写
EventLoopGroup workerGroup = new NioEventLoopGroup();
try{
//创建ServerBootstrap对象，启动 NIO服务端的辅助启动类
ServerBootstrap b = new ServerBootstrap();
b.group(bossGroup, workerGroup).
//设置为NIO
channel(NioServerSocketChannel.class)
.option(ChannelOption.SO_BACKLOG, 1024)
.handler(new LoggingHandler(LogLevel.INFO))
.childHandler(new ChildChannelHandler());

//绑定端口，同步等待成功
ChannelFuture f = b.bind(port).sync();

//等待服务器监听端口关闭
f.channel().closeFuture().sync();

}finally{
//释放线程池资源
bossGroup.shutdownGracefully();
workerGroup.shutdownGracefully();
}

}

private class ChildChannelHandler extends ChannelInitializer<SocketChannel>{

@Override
protected void initChannel(SocketChannel ch) throws Exception {
//处理半包问题
ch.pipeline().addLast(new ProtobufVarint32FrameDecoder());
//添加ProtobufDecoder解码器
ch.pipeline().addLast(new ProtobufDecoder(SubscribeReqProto.SubscribeReq.getDefaultInstance()));
ch.pipeline().addLast(new ProtobufVarint32LengthFieldPrepender());
ch.pipeline().addLast(new ProtobufEncoder());
ch.pipeline().addLast(new SubReqServerHandler());

}
}

public static void main(String[] args) throws Exception {

int port = 8080;
if(args != null && args.length>0){
try{
port = Integer.valueOf(args[0]);
}catch(Exception e){
//采用默认值
}
}
new SubReqServer().bind(port);
}

}

5.Netty服务端核心处理类

package com.phei.netty.protobuf;

import java.util.Date;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
/**
* 服务端核心处理类
* @author renhj
*
*/
public class SubReqServerHandler extends ChannelHandlerAdapter {

private int counter;

@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {

SubscribeReqProto.SubscribeReq req = (SubscribeReqProto.SubscribeReq)msg;
if("Lilinfeng".equalsIgnoreCase(req.getUserName())){
System.out.println("Server accept client subsrcibe req :["+req.toString()+"]");
ctx.writeAndFlush(resp(req.getSubReqID()));
}

}

private SubscribeRespProto.SubscribeResp resp(int subReqID){
SubscribeRespProto.SubscribeResp.Builder builder = SubscribeRespProto.SubscribeResp.newBuilder();
builder.setSubReqID(subReqID);
builder.setRespCode(0);
builder.setDesc("Netty book succeed, 3 days later , sent to the designated address ");
return builder.build();
}

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

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

}

6.Netty客户端类

package com.phei.netty.protobuf;

import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.DelimiterBasedFrameDecoder;
import io.netty.handler.codec.LineBasedFrameDecoder;
import io.netty.handler.codec.protobuf.ProtobufDecoder;
import io.netty.handler.codec.protobuf.ProtobufEncoder;
import io.netty.handler.codec.protobuf.ProtobufVarint32FrameDecoder;
import io.netty.handler.codec.protobuf.ProtobufVarint32LengthFieldPrepender;
import io.netty.handler.codec.string.StringDecoder;

/**
* 客服端
* @author renhj
*
*/

public class SubReqClient {

public void connect(int port , String host) throws Exception{

//配置客户端NIO线程组
EventLoopGroup group = new NioEventLoopGroup();
try{
Bootstrap b = new Bootstrap();
b.group(group).channel(NioSocketChannel.class)
.option(ChannelOption.TCP_NODELAY, true)
.handler(new ChannelInitializer<SocketChannel>(){

@Override
public void initChannel(SocketChannel ch) throws Exception{
//处理半包问题
ch.pipeline().addLast(new ProtobufVarint32FrameDecoder());
//添加ProtobufDecoder解码器
ch.pipeline().addLast(new ProtobufDecoder(SubscribeRespProto.SubscribeResp.getDefaultInstance()));
ch.pipeline().addLast(new ProtobufVarint32LengthFieldPrepender());
ch.pipeline().addLast(new ProtobufEncoder());
ch.pipeline().addLast(new SubReqClientHandler());
}
});
//发起异步连接操作
ChannelFuture f = b.connect(host, port).sync();

//等待客户端链路关闭
f.channel().closeFuture().sync();

}finally{
//释放NIO线程
group.shutdownGracefully();
}

}
public static void main(String[] args) throws Exception{

int port = 8080;
if(args !=null && args.length>0){
try{
port = Integer.valueOf(args[0]);
}catch(Exception e){

}
}
new SubReqClient().connect(port, "127.0.0.1");
}
}

7.Netty客户端核心处理类

package com.phei.netty.protobuf;

import java.util.ArrayList;
import java.util.List;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;

/**
* 客户端核心处理类
* @author renhj
*
*/
public class SubReqClientHandler extends ChannelHandlerAdapter {

public SubReqClientHandler(){

}

@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {

for(int i=0;i<10;i++){
ctx.write(subReq(i));
}
ctx.flush();
}

private SubscribeReqProto.SubscribeReq subReq(int i){
SubscribeReqProto.SubscribeReq.Builder builder = SubscribeReqProto.SubscribeReq.newBuilder();
builder.setSubReqID(i);
builder.setUserName("Lilinfeng");
builder.setProductName("Netty Book For Protobuf");
List<String> address = new ArrayList<String>();
address.add("NanJing YuHuaTai");
address.add("BeiJing LiuLiChang");
builder.addAllAddress(address);
return builder.build();
}

@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {

System.out.println("Receive server response : ["+msg+"]");

}

@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {

//释放资源
ctx.close();
}

}

8.运行结果