基于Netty框架的JT809上级平台验证实现

  基于netty3的JT809协议验证实现。程序可以接收下级平台发送的业务报文，并转换成POJO对象。程序只处理了两个业务类型：下级平台登录、主链路连接保持消息。没有实现从链路的建立。

  数据流：下级平台-->LoggingHandler-->Decoder-->Message-->BusiHandler-->Message-->Encoder-->LoggingHandler-->下级平台。

• LoggingHandler是Netty框架提供的日志Handler，可以在控制台显示出站、入站的数据，方便调试。
• Decoder负责报文数据的完整性处理，并转换字节流为报文POJO对象。
• Message为自定义的JT809协议POJO对象
• BusiHandler为业务处理类
• Encoder负责将报文POJO对象拼装成ChannelBuffer对象传输
• Util.crc16是从网上找的CRC校验方法

由于是技术验证，代码中的一些值是写死的。

package test809;

import java.net.InetSocketAddress;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledThreadPoolExecutor;
import java.util.concurrent.TimeUnit;

import org.jboss.netty.bootstrap.ServerBootstrap;
import org.jboss.netty.channel.ChannelFactory;
import org.jboss.netty.channel.ChannelPipeline;
import org.jboss.netty.channel.ChannelPipelineFactory;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.channel.SimpleChannelHandler;
import org.jboss.netty.channel.socket.nio.NioServerSocketChannelFactory;
import org.jboss.netty.handler.logging.LoggingHandler;
import org.jboss.netty.logging.InternalLogLevel;

public class JTServer {
	public static void main(String args[]) {
		ChannelFactory factory = new NioServerSocketChannelFactory(Executors.newCachedThreadPool(),
				Executors.newCachedThreadPool());

		ServerBootstrap bootstrap = new ServerBootstrap(factory);

		bootstrap.setPipelineFactory(new ChannelPipelineFactory() {
			public ChannelPipeline getPipeline() {
				ChannelPipeline pipeline = Channels.pipeline();
				pipeline.addLast("loging", new LoggingHandler(InternalLogLevel.INFO));
				pipeline.addLast("decoder", new Decoder());
				pipeline.addLast("encoder", new Encoder());
				pipeline.addLast("busiHandler", new BusiHandler());
				
				return pipeline;
			}
		});

		bootstrap.setOption("child.tcpNoDelay", true);
		bootstrap.setOption("child.keepAlive", true);

		bootstrap.bind(new InetSocketAddress(8001));
		
		System.out.println("JTServer startup ....");
	}
	
}

package test809;

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.handler.codec.frame.FrameDecoder;

public class Decoder extends FrameDecoder{

	@Override
	protected Object decode(ChannelHandlerContext ctx, Channel channel, ChannelBuffer buffer) throws Exception {
		// TODO Auto-generated method stub
		
		int head = buffer.getByte(0);
		int tail = buffer.getByte(buffer.capacity()-1);
		System.out.println(buffer.getByte(buffer.capacity()-1));
		System.out.println(buffer.getByte(0));
		
		if(!(head == Message.MSG_HEAD && tail == Message.MSG_TAIL)){
			return null;
		}
		
		//跳过头标识
		buffer.skipBytes(1);
		//读取报文长度（目前有不一致情况）
		
		Message msg = this.buildMessage(buffer);
		return msg;
	}
	
	
	private Message buildMessage(ChannelBuffer buffer){
		Message msg = new Message();
		//读取报文长度（目前有不一致情况）
		msg.setMsgLength(buffer.readUnsignedInt());
		msg.setMsgSn(buffer.readInt());//4 byte
		msg.setMsgId(buffer.readUnsignedShort());//2 byte
		msg.setMsgGesscenterId(buffer.readUnsignedInt());//4 byte
		msg.setVersionFlag(buffer.readBytes(3).array());//3 byte
		msg.setEncryptFlag(buffer.readUnsignedByte());//1 byte
		msg.setEncryptKey(buffer.readUnsignedInt());//4 byte
		ChannelBuffer bodyBytes = buffer.readBytes(buffer.readableBytes()-2-1);//数据体为变长字节		
		msg.setMsgBody(bodyBytes);
		msg.setCrcCode(buffer.readUnsignedShort());//2 byte
		//跳过尾标识
		buffer.skipBytes(1);//1 byte
		//buffer.readByte();
		System.out.println("after build message readable bytes:"+buffer.readableBytes());
		return msg;
	}

	
	
}

package test809;

import java.nio.charset.Charset;

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.ChannelStateEvent;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.channel.SimpleChannelHandler;

public class BusiHandler extends SimpleChannelHandler {

	@Override
	public void messageReceived(ChannelHandlerContext ctx, MessageEvent e) throws Exception {
		// TODO Auto-generated method stub
		Message msg = (Message) e.getMessage();
		switch (msg.getMsgId()) {
		case 0x1001:
			login(msg, ctx, e);
			break;
		case 0x1005:
			System.out.println("主链路连接保持请求消息。");
			heartBeat(msg, ctx, e);
			break;

		default:
			break;
		}
	}

	private void login(Message msg, ChannelHandlerContext ctx, MessageEvent e) {
		int userId = msg.getMsgBody().readInt();
		String passWord = msg.getMsgBody().readBytes(8).toString(Charset.forName("GBK"));
		String ip = msg.getMsgBody().readBytes(32).toString(Charset.forName("GBK"));
		int port = msg.getMsgBody().readUnsignedShort();
		msg.getMsgBody().clear();
		System.out.println(userId);
		System.out.println(passWord);
		System.out.println(ip);
		System.out.println(port);
		
		Message msgRep = new Message(0x1002);
		ChannelBuffer buffer = ChannelBuffers.buffer(5);
		buffer.writeByte(0x00);
		
		//校验码，临时写死
		buffer.writeInt(1111);
		msgRep.setMsgBody(buffer);
		ChannelFuture f = e.getChannel().write(msgRep);
		
		// f.addListener(ChannelFutureListener.CLOSE);
	}
	
	private void heartBeat(Message msg, ChannelHandlerContext ctx, MessageEvent e){
		Message msgRep = new Message(0x1006);
		ChannelBuffer buffer = ChannelBuffers.buffer(0);
		msgRep.setMsgBody(buffer);
		ChannelFuture f = e.getChannel().write(msgRep);
	}


}

package test809;

import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.ChannelBuffers;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.Channels;
import org.jboss.netty.channel.ExceptionEvent;
import org.jboss.netty.channel.MessageEvent;
import org.jboss.netty.channel.SimpleChannelHandler;


public class Encoder extends SimpleChannelHandler{
	
	@Override
	public void writeRequested(ChannelHandlerContext ctx, MessageEvent e) throws Exception {
		// TODO Auto-generated method stub
		ChannelBuffer buffer = buildMessage((Message) e.getMessage());;
		if(buffer != null){
			Channels.write(ctx, e.getFuture(), buffer);
		}
	}
	
	
	/**
	 * 生成下行报文
	 * @param msg
	 * @return
	 */
	private ChannelBuffer buildMessage(Message msg){
		int bodyLength = msg.getMsgBody().capacity();
		ChannelBuffer buffer = ChannelBuffers.buffer(bodyLength+Message.MSG_FIX_LENGTH);
		buffer.writeByte(Message.MSG_HEAD);  //1
		//--------------数据头----------
		buffer.writeInt(buffer.capacity());  //4
		buffer.writeInt(msg.getMsgSn());     //4
		buffer.writeShort(msg.getMsgId());   //2
		buffer.writeInt(1); //4
		buffer.writeBytes(msg.getVersionFlag());//3
		buffer.writeByte(0);//1
		buffer.writeInt(20000000);//4
		//--------------数据体----------
		buffer.writeBytes(msg.getMsgBody());
		//------------crc校验码---------
		byte[] b = ChannelBuffers.buffer(bodyLength+22).array();
		buffer.getBytes(1, b);
		int crcValue = Util.crc16(b);
		buffer.writeShort(crcValue);//2
		buffer.writeByte(Message.MSG_TAIL);//1
		System.out.println("before send ："+buffer);
		return buffer;
	}
	
}

package test809;

import org.jboss.netty.buffer.ChannelBuffer;

public class Message {
	public static final int MSG_HEAD = 0x5b;
	public static final int MSG_TAIL = 0x5d;
	
	//报文中除数据体外，固定的数据长度
	public static final int MSG_FIX_LENGTH = 26;
	
	//报文序列号，自增。
	private static int internalMsgNo = 0;
	private long msgLength, encryptFlag=1,  msgGesscenterId, encryptKey;
	private int crcCode,msgId,msgSn;
	private ChannelBuffer msgBody;
	private byte[] versionFlag = {0,0,1};
	
	//下行报文标识，值为1时，代表发送的数据；默认为0，代表接收的报文
	//private int downFlag = 0;
	
	public Message(){}
	
	public Message(int msgId){
		//下行报文需要填充报文序列号
		synchronized((Integer)internalMsgNo) {
			if(internalMsgNo == Integer.MAX_VALUE){
				internalMsgNo = 0;
			}
		}
		this.msgSn = ++internalMsgNo;
		this.msgId = msgId;
		//this.downFlag = 1;
	}

	public int getCrcCode() {
		return crcCode;
	}

	public void setCrcCode(int crcCode) {
		this.crcCode = crcCode;
	}

	public byte[] getVersionFlag() {
		return versionFlag;
	}

	public void setVersionFlag(byte[] versionFlagBytes) {
		this.versionFlag = versionFlagBytes;
	}

	public long getMsgLength() {
		return msgLength;
	}

	public void setMsgLength(long msgLength) {
		this.msgLength = msgLength;
	}

	public long getEncryptFlag() {
		return encryptFlag;
	}

	public void setEncryptFlag(int encryptFlag) {
		this.encryptFlag = encryptFlag;
	}

	public int getMsgSn() {
		return msgSn;
	}

	public void setMsgSn(int msgSn) {
		this.msgSn = msgSn;
	}

	public int getMsgId() {
		return msgId;
	}

	public void setMsgId(int msgId) {
		this.msgId = msgId;
	}

	public long getMsgGesscenterId() {
		return msgGesscenterId;
	}

	public void setMsgGesscenterId(long msgGesscenterId) {
		this.msgGesscenterId = msgGesscenterId;
	}

	public long getEncryptKey() {
		return encryptKey;
	}

	public void setEncryptKey(long encryptKey) {
		this.encryptKey = encryptKey;
	}

	public ChannelBuffer getMsgBody() {
		return msgBody;
	}

	public void setMsgBody(ChannelBuffer msgBody) {
		System.out.println("0x"+Integer.toHexString(this.msgId)+": "+msgBody.capacity()+" 字节数据体.");
		this.msgBody = msgBody;
	}

	@Override
	public String toString() {
		// TODO Auto-generated method stub
		return ("MSG_ID:" + this.msgId + " --> " + this.msgBody + " version flag:" + this.versionFlag + " encryptKey:"
				+ this.encryptKey + " crcCode:" + this.crcCode+" msgGesscenterId:"+this.msgGesscenterId);
	}
}

package test809;

public class Util {
	public static int crc16(byte[]... bytesArr) {
		int b = 0;
		int crc = 0xffff;

		for (byte[] d : bytesArr) {
			for (int i = 0; i < d.length; i++) {
				for (int j = 0; j < 8; j++) {
					b = ((d[i] << j) & 0x80) ^ ((crc & 0x8000) >> 8);
					crc <<= 1;
					if (b != 0)
						crc ^= 0x1021;
				}
			}
		}
		crc = ~crc;
		return crc;
	}
}