Netty4 and protocol buffer combined with a simple tutorial

Communication between projects is usually done using binary, small bandwidth, fast processing speed ~

Thanks to Netty author trustin Lee, let Netty naturally support protocol buffer.

This example uses netty4+protobuf-2.5.0, executes under Win7, and assumes that JDK and Maven have been installed.

1. Download and unzip Protoc-2.5.0-win32.zip and Protobuf-2.5.0.zip

2, to protobuf-2.5.0.zip installation directory Protobuf-2.5.0\java, execute MAVEN command: MVN package Jar:jar, will generate Target\protobuf-java-2.5.0.jar

3. Define Proto file Test.proto:

Package domain;

Option Java_package = "Com.server.domain";

Message Testpro {
Required String test = 1;
}

4. Copy the 2nd jar package to the Java file directory and run the following command to generate the Java file:

Protoc-2.5.0-win32.zip installation directory \protoc.exe--java_out=java file directory proto definition file directory \test.proto

5. Put the generated Protobuf-java-2.5.0.jar and Netty4 jar packages into the classpath of the project, and place the Java file generated by the 4th into the corresponding path of the project.

6. Writing server-side code

1), write handler class:

Import Io.netty.channel.ChannelHandlerContext;
Import Io.netty.channel.SimpleChannelInboundHandler;

public class Serverhandler extends Simplechannelinboundhandler<test.testpro> {
@Override
public void channelRead0 (Channelhandlercontext ctx, Test.testpro msg) throws Exception {
SYSTEM.OUT.PRINTLN ("Server:" + "Channelread:" + msg.gettest ());

Test.TestPro.Builder Builder = Test.TestPro.newBuilder ();
Builder.settest ("Received your message!");
Ctx.writeandflush (Builder.build ());
}
}

2), registration service, bound port:

Import Io.netty.bootstrap.ServerBootstrap;
Import Io.netty.channel.Channel;
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.nio.NioServerSocketChannel;
Import Io.netty.handler.codec.protobuf.ProtobufDecoder;
Import Io.netty.handler.codec.protobuf.ProtobufEncoder;

public class Server {

public static void Main (string[] args) {
Eventloopgroup Bosseventloopgroup = new Nioeventloopgroup ();
Eventloopgroup Workereventloopgroup = new Nioeventloopgroup ();
try {
Serverbootstrap serverbootstrap = new Serverbootstrap ();
Serverbootstrap.group (Bosseventloopgroup, Workereventloopgroup);
Serverbootstrap.channel (Nioserversocketchannel.class);
Serverbootstrap.childhandler (New channelinitializer<channel> () {
@Override
protected void Initchannel (Channel ch) throws Exception {
Ch.pipeline (). AddLast ("encoder", New Protobufencoder ());
Ch.pipeline (). AddLast ("Decoder", New Protobufdecoder (Test.TestPro.getDefaultInstance ()));
Ch.pipeline (). AddLast ("handler", New Serverhandler ());
};
});
Serverbootstrap.childoption (channeloption.so_keepalive, true);
Channelfuture channelfuture = Serverbootstrap.bind (8888). sync ();
Channelfuture.channel (). Closefuture (). sync ();
} catch (Exception e) {
E.printstacktrace ();
} finally {
Bosseventloopgroup.shutdowngracefully ();
Workereventloopgroup.shutdowngracefully ();
}
}
}

7. Writing client-side code

1), define the client side of the handler class:

Import Io.netty.channel.ChannelHandlerContext;
Import Io.netty.channel.SimpleChannelInboundHandler;

public class ClientHandler extends Simplechannelinboundhandler<test.testpro> {

@Override
protected void channelRead0 (Channelhandlercontext ctx, Test.testpro msg) throws Exception {
SYSTEM.OUT.PRINTLN ("Client:" + "Channelread:" + msg.gettest ());
}
}

2), establish client-side to server-side connection

Import Java.io.BufferedReader;
Import Java.io.InputStreamReader;

Import Io.netty.bootstrap.Bootstrap;
Import Io.netty.channel.Channel;
Import Io.netty.channel.ChannelInitializer;
Import Io.netty.channel.EventLoopGroup;
Import Io.netty.channel.nio.NioEventLoopGroup;
Import Io.netty.channel.socket.nio.NioSocketChannel;
Import Io.netty.handler.codec.protobuf.ProtobufDecoder;
Import Io.netty.handler.codec.protobuf.ProtobufEncoder;
Import Io.netty.handler.codec.string.StringDecoder;
Import Io.netty.handler.codec.string.StringEncoder;

public class Client {

public static void Main (string[] args) {
Eventloopgroup Eventloopgroup = new Nioeventloopgroup ();
try {
Bootstrap Bootstrap = new Bootstrap ();
Bootstrap.group (Eventloopgroup);
Bootstrap.channel (Niosocketchannel.class);
Bootstrap.handler (New channelinitializer<channel> () {
@Override
protected void Initchannel (Channel ch) throws Exception {
Ch.pipeline (). AddLast ("encoder", New Protobufencoder ());
Ch.pipeline (). AddLast ("Decoder", New Protobufdecoder (Test.TestPro.getDefaultInstance ()));
Ch.pipeline (). AddLast ("handler", New ClientHandler ());
};
});

Channel ch = bootstrap.connect ("127.0.0.1", 8888). Sync (). Channel ();

Console input
BufferedReader in = new BufferedReader (new InputStreamReader (system.in));
for (;;) {
String line = In.readline ();
if (line = = NULL | | "". Equals (line)) {
Continue
}
Test.TestPro.Builder Builder = Test.TestPro.newBuilder ();
Builder.settest (line);
Ch.writeandflush (Builder.build ());
}
} catch (Exception e) {
E.printstacktrace ();
} finally {
Eventloopgroup.shutdowngracefully ();
}
}
}

Getting Started tutorial, welcome to shoot bricks.

Recommended additional reference Tutorials: protocol and Netty Data http://blog.csdn.net/goldenfish1919/article/details/6719276

Netty4 and protocol buffer combined with a simple tutorial