网络编程 -- RPC实现原理 -- Netty -- 迭代版本V3 -- 编码解码

时间:2023-03-09 00:51:32
网络编程 -- RPC实现原理 -- Netty -- 迭代版本V3 -- 编码解码

 网络编程 -- RPC实现原理 -- 目录

  啦啦啦

V2——Netty -- pipeline.addLast(io.netty.handler.codec.MessageToMessageCodec<INBOUND_IN, OUTBOUND_IN>) 覆写编码解码方法。

 pipeline相当于拦截器。在pipeline中添加MessageToMessageCodec接口的实现类,该接口的实现类中的encode()方法自动将发送的Object对象转换为ByteBuf,decode()方法自动将接收的ByteBuf对象转换为Object

 

  Class : Server

package lime.pri.limeNio.netty.netty03;

import java.net.InetSocketAddress;
import java.util.Date;
import java.util.List; import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializerFeature; import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
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.MessageToMessageCodec;
import io.netty.util.CharsetUtil;
import lime.pri.limeNio.netty.netty03.entity.User; public class Server { public static void main(String[] args) throws Exception {
ServerBootstrap serverBootstrap = new ServerBootstrap();
EventLoopGroup boss = new NioEventLoopGroup();
EventLoopGroup worker = new NioEventLoopGroup();
serverBootstrap.group(boss, worker);
serverBootstrap.channel(NioServerSocketChannel.class);
serverBootstrap.childHandler(new ChannelInitializer<SocketChannel>() { @Override
protected void initChannel(SocketChannel ch) throws Exception {
ChannelPipeline pipeline = ch.pipeline();
pipeline.addLast(new MessageToMessageCodec<ByteBuf, Object>() {
@Override
protected void encode(ChannelHandlerContext ctx, Object msg, List<Object> out) throws Exception {
System.out.println("-- -- 服务端编码");
out.add(Unpooled.buffer().writeBytes(JSON.toJSONString(msg,SerializerFeature.WriteClassName).getBytes(CharsetUtil.UTF_8)));
} @Override
protected void decode(ChannelHandlerContext ctx, ByteBuf msg, List<Object> out) throws Exception {
System.out.println("-- -- 服务端解码");
out.add(JSON.parse(msg.toString(CharsetUtil.UTF_8)));
}
}).addLast(new ChannelHandlerAdapter() { @Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
System.out.println("客户端请求数据:" + msg);
String request = (String) msg;
Object response = "请求参数不正确";
if("Query Date".equalsIgnoreCase(request)){
response = "当前系统时间:" + new Date().toString();
}else if("Query User".equalsIgnoreCase(request)){
response = new User(1,"lime",new Date());
}
ChannelFuture channelFuture = ctx.writeAndFlush(response);
channelFuture.addListener(ChannelFutureListener.FIRE_EXCEPTION_ON_FAILURE);
channelFuture.addListener(ChannelFutureListener.CLOSE_ON_FAILURE);
channelFuture.addListener(ChannelFutureListener.CLOSE);
}
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
cause.printStackTrace();
} });
} });
ChannelFuture channelFuture = serverBootstrap.bind(new InetSocketAddress(9999)).sync();
channelFuture.channel().closeFuture().sync();
boss.close();
worker.close();
}
}

  Class : Client

package lime.pri.limeNio.netty.netty03;

import java.net.InetSocketAddress;
import java.util.List; import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.serializer.SerializerFeature; import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelFutureListener;
import io.netty.channel.ChannelHandlerAdapter;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInitializer;
import io.netty.channel.ChannelPipeline;
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.MessageToMessageCodec;
import io.netty.util.CharsetUtil; public class Client { public static void main(String[] args) throws Exception {
for (int i = 0; i < 10; i++) {
new Thread() {
{
setDaemon(false);
} public void run() {
try {
client();
} catch (Exception e) {
e.printStackTrace();
}
};
}.start();
Thread.sleep(1000);
}
} private static void client() throws Exception {
Bootstrap bootstrap = new Bootstrap();
EventLoopGroup worker = new NioEventLoopGroup();
bootstrap.group(worker);
bootstrap.channel(NioSocketChannel.class);
bootstrap.handler(new ChannelInitializer<SocketChannel>() { @Override
protected void initChannel(SocketChannel ch) throws Exception {
ChannelPipeline pipeline = ch.pipeline();
pipeline.addLast(new MessageToMessageCodec<ByteBuf, Object>() { @Override
protected void encode(ChannelHandlerContext ctx, Object msg, List<Object> out) throws Exception {
System.out.println("-- -- 客户端编码");
out.add(Unpooled.buffer().writeBytes(JSON.toJSONString(msg, SerializerFeature.WriteClassName).getBytes(CharsetUtil.UTF_8)));
} @Override
protected void decode(ChannelHandlerContext ctx, ByteBuf msg, List<Object> out) throws Exception {
System.out.println("-- -- 客户端解码");
out.add(JSON.parse(msg.toString(CharsetUtil.UTF_8)));
}
}).addLast(new ChannelHandlerAdapter() {
/**
* 默认只捕获网络连接异常
*/
@Override
public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
System.out.println(cause);
} /**
* 客户端发送经过JSON编码的byteBuf
*/
@Override
public void channelActive(ChannelHandlerContext ctx) throws Exception {
String request = null;
switch ((int) (Math.random() * 10) % 3) {
case 0:
request = "Query Date";
break;
case 1:
request = "Query User";
break; default:
request = "Query What?";
break;
}
ChannelFuture channelFuture = ctx.writeAndFlush(request);
channelFuture.addListener(ChannelFutureListener.FIRE_EXCEPTION_ON_FAILURE);
channelFuture.addListener(ChannelFutureListener.CLOSE_ON_FAILURE);
} @Override
public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
System.out.println("服务端响应数据 --> " + msg);
} });
}
});
ChannelFuture channelFuture; channelFuture = bootstrap.connect(new InetSocketAddress(9999)).sync();
channelFuture.channel().closeFuture().sync();
worker.close();
}
}

啦啦啦