架构师养成记--21.netty编码解码

背景

作为网络传输框架，免不了哟啊传输对象，对象在传输之前就要序列化，这个序列化的过程就是编码过程。接收到编码后的数据就需要解码，还原传输的数据。

代码

工厂类

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;
    }
}

服务器端

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();
        
    }
}

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();
    }

    
    
}

客户端

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();
    }
}

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();
    }
    
}

工具类（压缩文件）

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

public class GzipUtils {

    public static byte[] gzip(byte[] data) throws Exception{
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        GZIPOutputStream gzip = new GZIPOutputStream(bos);
        gzip.write(data);
        gzip.finish();
        gzip.close();
        byte[] ret = bos.toByteArray();
        bos.close();
        return ret;
    }
    
    public static byte[] ungzip(byte[] data) throws Exception{
        ByteArrayInputStream bis = new ByteArrayInputStream(data);
        GZIPInputStream gzip = new GZIPInputStream(bis);
        byte[] buf = new byte[1024];
        int num = -1;
        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        while((num = gzip.read(buf, 0 , buf.length)) != -1 ){
            bos.write(buf, 0, num);
        }
        gzip.close();
        bis.close();
        byte[] ret = bos.toByteArray();
        bos.flush();
        bos.close();
        return ret;
    }
    
    public static void main(String[] args) throws Exception{
        
        //读取文件
        String readPath = System.getProperty("user.dir") + File.separatorChar + "sources" +  File.separatorChar + "006.jpg";
        File file = new File(readPath);  
        FileInputStream in = new FileInputStream(file);  
        byte[] data = new byte[in.available()];  
        in.read(data);  
        in.close();  
        
        System.out.println("文件原始大小:" + data.length);
        //测试压缩
        
        byte[] ret1 = GzipUtils.gzip(data);
        System.out.println("压缩之后大小:" + ret1.length);
        
        byte[] ret2 = GzipUtils.ungzip(ret1);
        System.out.println("还原之后大小:" + ret2.length);
        
        //写出文件
        String writePath = System.getProperty("user.dir") + File.separatorChar + "receive" +  File.separatorChar + "006.jpg";
        FileOutputStream fos = new FileOutputStream(writePath);
        fos.write(ret2);
        fos.close();        
        
        
    }
    
    
    
}

数据对象

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;
    }
    

}