最简单的UDPServer网关转发程序实现

项目简介

本文将介绍一个简单的UDPServer网关转发程序，该程序用于接收指定端口的UDP数据包并将其转发到指定目标IP地址和端口。本程序使用Spring Boot和Netty技术，能够高效处理UDP数据包转发任务。

项目结构

1. 项目依赖管理

项目依赖主要包括以下几项：

Spring Boot：用于程序的快速开发和配置管理。

Netty：用于高效处理UDP数据包。

Lombok：简化Java代码编写。

Apache Commons Lang：用于字符串操作。

项目依赖管理文件如下：


       
    
     4.0.0
        
    
     com.tiza.leo
        
    
     UdpGetwayForwardByNetty
        
    
     1.0-SNAPSHOT
        
            
                 
                      
       
        org.apache.maven.plugins
                       
       
        maven-compiler-plugin
                       
                           
        8                    
        
         8
                        
                   
                  
                      
       
        org.springframework.boot
                       
       
        spring-boot-maven-plugin
                       
                           
        
         com.tiza.leo.UdpGetwayForwardByNetty.Boot
                            
         
          
           
           
            repackage
            
           
          
                        
                   
              
         
        
            
                 
                      
       
        org.springframework.boot
                       
       
        spring-boot-dependencies
                       
       
        2.2.1.RELEASE
                       
       
        pom
                       
       
        import
                   
              
         
        
            
                 
      
       org.springframework.boot
                  
      
       spring-boot-starter-actuator
              
             
                 
      
       io.netty
                  
      
       netty-all
                  
      
       4.1.42.Final
              
             
                 
      
       org.project.lombok
                  
      
       lombok
                  
      
       1.18.12
              
             
                 
      
       org.apache.commons
                  
      
       commons-lang3
                  
      
       3.11

2. 项目配置

项目配置文件中定义了以下关键参数：

spring: profiles: active: devgatewayinPort: 2222outIp: 192.168.35.1outPort: 3333

核心技术实现

1. 项目启动类

package com.tiza.leo.UdpGetwayForwardByNetty;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.boot.ApplicationArguments;import org.springframework.boot.ApplicationRunner;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;@SpringBootApplicationpublic class Boot implements ApplicationRunner {    @Autowired    private GatewayDeamon gatewayDeamon;    public static void main(String[] args) {        SpringApplication.run(Boot.class, args);    }    @Override    public void run(ApplicationArguments args) throws Exception {        gatewayDeamon.start();    }}

2. 网关处理逻辑

package com.tiza.leo.UdpGetwayForwardByNetty.handler;import io.netty.buffer.ByteBuf;import io.netty.channel.ChannelHandler;import io.netty.channel.ChannelHandlerContext;import io.netty.channel.ChannelInboundHandlerAdapter;import io.netty.channel.socket.DatagramPacket;import lombok.extern.slf4j.Slf4j;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.core.env.Environment;import java.net.InetSocketAddress;@Slf4j@Component(value = "receiveHandler", condition = "beanName")class ReceiveHandler extends ChannelInboundHandlerAdapter {    @Autowired    private Environment env;    @Override    public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {        if (msg instanceof DatagramPacket) {            DatagramPacket datagramPacketIn = (DatagramPacket) msg;            ByteBuf buf = datagramPacketIn.copy().content();            buf.skipBytes(3);            InetSocketAddress address = new InetSocketAddress(env.getProperty("gateway.outIp"), Integer.parseInt(env.getProperty("gateway.outPort")));            DatagramPacket datagramPacketOut = new DatagramPacket(buf, address);            ctx.channel().writeAndFlush(datagramPacketOut).sync();            datagramPacketIn.release();        }    }}

3. 网关启动类

package com.tiza.leo.UdpGetwayForwardByNetty.deamon;import com.tiza.leo.UdpGetwayForwardByNetty.handler.ReceiveHandler;import io.netty.bootstrap.Bootstrap;import io.netty.channel.ChannelFuture;import io.netty.channel.ChannelInitializer;import io.netty.channel.ChannelOption;import io.netty.channel.ChannelPipeline;import io.netty.channel.nio.NioEventLoopGroup;import io.netty.channel.socket.nio.NioDatagramChannel;import lombok.extern.slf4j.Slf4j;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.boot.autoconfigure.couchbase.CouchbaseProperties;import org.springframework.core.env.Environment;import org.springframework.stereotype.Service;@Slf4j@Serviceclass GatewayDeamon {    @Autowired    private Environment env;    @Autowired    private ReceiveHandler receiveHandler;    public void start() {        NioEventLoopGroup bossGroup = new NioEventLoopGroup();        NioEventLoopGroup workGroup = new NioEventLoopGroup();        Integer port = env.getRequiredProperty("gateway.inPort", Integer.class);        log.info("绑定udp端口{}", port);        try {            Bootstrap bootstrap = new Bootstrap();            bootstrap.group(bossGroup)                    .channel(NioDatagramChannel.class)                    .option(ChannelOption.SO_BROADCAST, true)                    .option(ChannelOption.SO_RCVBUF, 1024 * 2048)                    .handler(new ChannelInitializer() {                        @Override                        protected void initChannel(NioDatagramChannel channel) throws Exception {                            ChannelPipeline pipeline = channel.pipeline();                            pipeline.addLast("receive", receiveHandler);                        }                    });            ChannelFuture future = bootstrap.bind(port).sync();            future.channel().closeFuture().sync();        } catch (Exception e) {            log.error(e.getMessage(), e);        } finally {            bossGroup.shutdownGracefully();            workGroup.shutdownGracefully();        }    }}