netty

概念：

　　是一个nio框架的实现，是高可靠，高性能的一个端到端数据传输框架。

　　Netty的“quick and easy(高性能和简单易用)”并不意味着编写的程序的性能和可维护性会受到影响。从Netty中实现的协议如FTP，SMTP，HTTP，WebSocket，SPDY以及各种二进制和基于文本的传统协议中获得的经验导致Netty的创始人要非常小心它的设计。Netty成功的提供了易于开发，高性能和高稳定性，以及较强的扩展性。

　

１、server端

import io.netty.bootstrap.ServerBootstrap;

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.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;


public class Server {


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

EventLoopGroup pGroup = new NioEventLoopGroup();
EventLoopGroup cGroup = new NioEventLoopGroup();

ServerBootstrap b = new ServerBootstrap();
b.group(pGroup, cGroup)
.channel(NioServerSocketChannel.class)
.option(ChannelOption.SO_BACKLOG, 1024)
//设置日志
.handler(new LoggingHandler(LogLevel.INFO))
.childHandler(new ChannelInitializer<SocketChannel>() {
protected void initChannel(SocketChannel sc) throws Exception {
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingDecoder());
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingEncoder());
sc.pipeline().addLast(new ServerHandler());
}
});

ChannelFuture cf = b.bind(8765).sync();

cf.channel().closeFuture().sync();
pGroup.shutdownGracefully();
cGroup.shutdownGracefully();

}
}

２、客户端

　　客户端只需要一个接收连接的线程组。

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelInitializer;
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 java.io.File;
import java.io.FileInputStream;


import bhz.utils.GzipUtils;


public class Client {

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

EventLoopGroup group = new NioEventLoopGroup();
Bootstrap b = new Bootstrap();
b.group(group)
.channel(NioSocketChannel.class)
.handler(new ChannelInitializer<SocketChannel>() {
@Override
protected void initChannel(SocketChannel sc) throws Exception {
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingDecoder());
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingEncoder());
sc.pipeline().addLast(new ClientHandler());
}
});

ChannelFuture cf = b.connect("127.0.0.1", 8765).sync();

for(int i = 0; i < 5; i++ ){
Req req = new Req();
req.setId("" + i);
req.setName("pro" + i);
req.setRequestMessage("数据信息" + i);
String path = System.getProperty("user.dir") + File.separatorChar + "sources" +  File.separatorChar + "001.jpg";
File file = new File(path);
       FileInputStream in = new FileInputStream(file);  
       byte[] data = new byte[in.available()];  
       in.read(data);  
       in.close(); 
req.setAttachment(GzipUtils.gzip(data));
cf.channel().writeAndFlush(req);
}


cf.channel().closeFuture().sync();
group.shutdownGracefully();
}
}

3、server handle的实现

 import io.netty.channel.ChannelHandlerAdapter;

import io.netty.channel.ChannelHandlerContext;

import java.io.File;
import java.io.FileOutputStream;

import bhz.utils.GzipUtils;


public class ServerHandler extends ChannelHandlerAdapter{


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

}


@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
Req req = (Req)msg;
System.out.println("Server : " + req.getId() + ", " + req.getName() + ", " + req.getRequestMessage());
byte[] attachment = GzipUtils.ungzip(req.getAttachment());

String path = System.getProperty("user.dir") + File.separatorChar + "receive" +  File.separatorChar + "001.jpg";
        FileOutputStream fos = new FileOutputStream(path);
        fos.write(attachment);
        fos.close();

Resp resp = new Resp();
resp.setId(req.getId());
resp.setName("resp" + req.getId());
resp.setResponseMessage("响应内容" + req.getId());
ctx.writeAndFlush(resp);//.addListener(ChannelFutureListener.CLOSE);
}


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

}


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

}

４、ClientHandler

import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
import io.netty.util.ReferenceCountUtil;


public class ClientHandler extends ChannelHandlerAdapter{

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

}


@Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
try {
Resp resp = (Resp)msg;
System.out.println("Client : " + resp.getId() + ", " + resp.getName() + ", " + resp.getResponseMessage());
} finally {
ReferenceCountUtil.release(msg);
}
}


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

}


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

}

５、MarshallingCodeCFactory

import io.netty.handler.codec.marshalling.DefaultMarshallerProvider;
import io.netty.handler.codec.marshalling.DefaultUnmarshallerProvider;
import io.netty.handler.codec.marshalling.MarshallerProvider;
import io.netty.handler.codec.marshalling.MarshallingDecoder;
import io.netty.handler.codec.marshalling.MarshallingEncoder;
import io.netty.handler.codec.marshalling.UnmarshallerProvider;


import org.jboss.marshalling.MarshallerFactory;
import org.jboss.marshalling.Marshalling;
import org.jboss.marshalling.MarshallingConfiguration;


/**
 * Marshalling工厂
 * @author（alienware）
 * @since 2014-12-16
 */
public final class MarshallingCodeCFactory {


    /**
     * 创建Jboss Marshalling解码器MarshallingDecoder
     * @return MarshallingDecoder
     */
    public static MarshallingDecoder buildMarshallingDecoder() {
    //首先通过Marshalling工具类的精通方法获取Marshalling实例对象 参数serial标识创建的是java序列化工厂对象。
final MarshallerFactory marshallerFactory = Marshalling.getProvidedMarshallerFactory("serial");
//创建了MarshallingConfiguration对象，配置了版本号为5 
final MarshallingConfiguration configuration = new MarshallingConfiguration();
configuration.setVersion(5);
//根据marshallerFactory和configuration创建provider
UnmarshallerProvider provider = new DefaultUnmarshallerProvider(marshallerFactory, configuration);
//构建Netty的MarshallingDecoder对象，俩个参数分别为provider和单个消息序列化后的最大长度
MarshallingDecoder decoder = new MarshallingDecoder(provider, 1024 * 1024 * 1);
return decoder;
    }


    /**
     * 创建Jboss Marshalling编码器MarshallingEncoder
     * @return MarshallingEncoder
     */
    public static MarshallingEncoder buildMarshallingEncoder() {
final MarshallerFactory marshallerFactory = Marshalling.getProvidedMarshallerFactory("serial");
final MarshallingConfiguration configuration = new MarshallingConfiguration();
configuration.setVersion(5);
MarshallerProvider provider = new DefaultMarshallerProvider(marshallerFactory, configuration);
//构建Netty的MarshallingEncoder对象，MarshallingEncoder用于实现序列化接口的POJO对象序列化为二进制数组
MarshallingEncoder encoder = new MarshallingEncoder(provider);
return encoder;
    }
}

６、Req和Resp

import java.io.Serializable;
public class Req implements Serializable{
private static final long  SerialVersionUID = 1L;

private String id ;
private String name ;
private String requestMessage ;
private byte[] attachment;

public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getRequestMessage() {
return requestMessage;
}
public void setRequestMessage(String requestMessage) {
this.requestMessage = requestMessage;
}
public byte[] getAttachment() {
return attachment;
}
public void setAttachment(byte[] attachment) {
this.attachment = attachment;
}

} 

import java.io.Serializable;

public class Resp implements Serializable{

private static final long serialVersionUID = 1L;

private String id;
private String name;
private String responseMessage;

public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getResponseMessage() {
return responseMessage;
}
public void setResponseMessage(String responseMessage) {
this.responseMessage = responseMessage;
}



}

7、通过引入jboss的marshalling来实现来实现序列化

　　 .childHandler(new ChannelInitializer<SocketChannel>() {
protected void initChannel(SocketChannel sc) throws Exception {
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingDecoder());
sc.pipeline().addLast(MarshallingCodeCFactory.buildMarshallingEncoder());
sc.pipeline().addLast(new ServerHandler());
}
});