JT808协议扫盲
- 1 数据类型
- 2 消息结构
- 3 消息头
解析
- 1 消息体实体类
- 2 字节数组到消息体实体类的转换
  - 21 消息转换器
  - 22 用到的工具类
    - 221 BCD操作工具类
    - 222 位操作工具类
- 3 和netty结合
  - 31 netty处理器链
  - 32 netty针对于JT808的消息处理器
  - 33 用到的其他类
demo级别java示例
注

本篇文章将介绍JT808协议的解析思路。
另请大神绕路，不喜勿喷！
先写个大致的思路,有疑问可以联系本人，联系方式：

emial: hylexus@163.com

1 JT808协议扫盲

1.1 数据类型

数据类型	描述及要求
BYTE	无符号单字节整形（字节， 8 位）
WORD	无符号双字节整形（字， 16 位）
DWORD	无符号四字节整形（双字， 32 位）
BYTE[n]	n 字节
BCD[n]	8421 码， n 字节
STRING	GBK 编码，若无数据，置空

1.2 消息结构

标识位	消息头	消息体	校验码	标识位
1byte(0x7e)	16byte		1byte	1byte(0x7e)

1.3 消息头

消息ID(0-1)   消息体属性(2-3)  终端手机号(4-9)  消息流水号(10-11)    消息包封装项(12-15)byte[0-1]   消息ID word(16)
byte[2-3]   消息体属性 word(16)bit[0-9]    消息体长度bit[10-12]  数据加密方式此三位都为 0，表示消息体不加密第 10 位为 1，表示消息体经过 RSA 算法加密其它保留bit[13]     分包1：消息体卫长消息，进行分包发送处理，具体分包信息由消息包封装项决定0：则消息头中无消息包封装项字段bit[14-15]  保留
byte[4-9]   终端手机号或设备ID bcd[6]根据安装后终端自身的手机号转换手机号不足12 位，则在前面补 0
byte[10-11]     消息流水号 word(16)按发送顺序从 0 开始循环累加
byte[12-15]     消息包封装项byte[0-1]   消息包总数(word(16))该消息分包后得总包数byte[2-3]   包序号(word(16))从 1 开始如果消息体属性中相关标识位确定消息分包处理,则该项有内容否则无该项

2 解析

整个消息体结构中最复杂的就是消息头了。

2.1 消息体实体类

以下是对整个消息体抽象出来的一个java实体类。

import java.nio.channels.Channel;public class PackageData {/*** 16byte 消息头*/protected MsgHeader msgHeader;// 消息体字节数组protected byte[] msgBodyBytes;/*** 校验码 1byte*/protected int checkSum;//记录每个客户端的channel,以便下发信息给客户端protected Channel channel;public MsgHeader getMsgHeader() {return msgHeader;}//TODO set 和 get 方法在此处省略//消息头public static class MsgHeader {// 消息IDprotected int msgId;/// ========消息体属性// byte[2-3]protected int msgBodyPropsField;// 消息体长度protected int msgBodyLength;// 数据加密方式protected int encryptionType;// 是否分包,true==>有消息包封装项protected boolean hasSubPackage;// 保留位[14-15]protected String reservedBit;/// ========消息体属性// 终端手机号protected String terminalPhone;// 流水号protected int flowId; =====消息包封装项// byte[12-15]protected int packageInfoField;// 消息包总数(word(16))protected long totalSubPackage;// 包序号(word(16))这次发送的这个消息包是分包中的第几个消息包, 从 1 开始protected long subPackageSeq; =====消息包封装项//TODO set 和 get 方法在此处省略}}

2.2 字节数组到消息体实体类的转换

2.2.1 消息转换器

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import cn.hylexus.jt808.util.BCD8421Operater;
import cn.hylexus.jt808.util.BitOperator;
import cn.hylexus.jt808.vo.PackageData;
import cn.hylexus.jt808.vo.PackageData.MsgHeader;public class MsgDecoder {private static final Logger log = LoggerFactory.getLogger(MsgDecoder.class);private BitOperator bitOperator;private BCD8421Operater bcd8421Operater;public MsgDecoder() {this.bitOperator = new BitOperator();this.bcd8421Operater = new BCD8421Operater();}//字节数组到消息体实体类public PackageData queueElement2PackageData(byte[] data) {PackageData ret = new PackageData();// 1. 16byte 或 12byte 消息头MsgHeader msgHeader = this.parseMsgHeaderFromBytes(data);ret.setMsgHeader(msgHeader);int msgBodyByteStartIndex = 12;// 2. 消息体// 有子包信息,消息体起始字节后移四个字节:消息包总数(word(16))+包序号(word(16))if (msgHeader.isHasSubPackage()) {msgBodyByteStartIndex = 16;}byte[] tmp = new byte[msgHeader.getMsgBodyLength()];System.arraycopy(data, msgBodyByteStartIndex, tmp, 0, tmp.length);ret.setMsgBodyBytes(tmp);// 3. 去掉分隔符之后，最后一位就是校验码// int checkSumInPkg =// this.bitOperator.oneByteToInteger(data[data.length - 1]);int checkSumInPkg = data[data.length - 1];int calculatedCheckSum = this.bitOperator.getCheckSum4JT808(data, 0, data.length - 1);ret.setCheckSum(checkSumInPkg);if (checkSumInPkg != calculatedCheckSum) {log.warn("检验码不一致,msgid:{},pkg:{},calculated:{}", msgHeader.getMsgId(), checkSumInPkg, calculatedCheckSum);}return ret;}private MsgHeader parseMsgHeaderFromBytes(byte[] data) {MsgHeader msgHeader = new MsgHeader();// 1. 消息ID word(16)// byte[] tmp = new byte[2];// System.arraycopy(data, 0, tmp, 0, 2);// msgHeader.setMsgId(this.bitOperator.twoBytesToInteger(tmp));msgHeader.setMsgId(this.parseIntFromBytes(data, 0, 2));// 2. 消息体属性 word(16)=================>// System.arraycopy(data, 2, tmp, 0, 2);// int msgBodyProps = this.bitOperator.twoBytesToInteger(tmp);int msgBodyProps = this.parseIntFromBytes(data, 2, 2);msgHeader.setMsgBodyPropsField(msgBodyProps);// [ 0-9 ] 0000,0011,1111,1111(3FF)(消息体长度)msgHeader.setMsgBodyLength(msgBodyProps & 0x1ff);// [10-12] 0001,1100,0000,0000(1C00)(加密类型)msgHeader.setEncryptionType((msgBodyProps & 0xe00) >> 10);// [ 13_ ] 0010,0000,0000,0000(2000)(是否有子包)msgHeader.setHasSubPackage(((msgBodyProps & 0x2000) >> 13) == 1);// [14-15] 1100,0000,0000,0000(C000)(保留位)msgHeader.setReservedBit(((msgBodyProps & 0xc000) >> 14) + "");// 消息体属性 word(16)<=================// 3. 终端手机号 bcd[6]// tmp = new byte[6];// System.arraycopy(data, 4, tmp, 0, 6);// msgHeader.setTerminalPhone(this.bcd8421Operater.bcd2String(tmp));msgHeader.setTerminalPhone(this.parseBcdStringFromBytes(data, 4, 6));// 4. 消息流水号 word(16) 按发送顺序从 0 开始循环累加// tmp = new byte[2];// System.arraycopy(data, 10, tmp, 0, 2);// msgHeader.setFlowId(this.bitOperator.twoBytesToInteger(tmp));msgHeader.setFlowId(this.parseIntFromBytes(data, 10, 2));// 5. 消息包封装项// 有子包信息if (msgHeader.isHasSubPackage()) {// 消息包封装项字段msgHeader.setPackageInfoField(this.parseIntFromBytes(data, 12, 4));// byte[0-1] 消息包总数(word(16))// tmp = new byte[2];// System.arraycopy(data, 12, tmp, 0, 2);// msgHeader.setTotalSubPackage(this.bitOperator.twoBytesToInteger(tmp));msgHeader.setTotalSubPackage(this.parseIntFromBytes(data, 12, 2));// byte[2-3] 包序号(word(16)) 从 1 开始// tmp = new byte[2];// System.arraycopy(data, 14, tmp, 0, 2);// msgHeader.setSubPackageSeq(this.bitOperator.twoBytesToInteger(tmp));msgHeader.setSubPackageSeq(this.parseIntFromBytes(data, 12, 2));}return msgHeader;}protected String parseStringFromBytes(byte[] data, int startIndex, int lenth) {return this.parseStringFromBytes(data, startIndex, lenth, null);}private String parseStringFromBytes(byte[] data, int startIndex, int lenth, String defaultVal) {try {byte[] tmp = new byte[lenth];System.arraycopy(data, startIndex, tmp, 0, lenth);return new String(tmp, "UTF-8");} catch (Exception e) {log.error("解析字符串出错:{}", e.getMessage());e.printStackTrace();return defaultVal;}}private String parseBcdStringFromBytes(byte[] data, int startIndex, int lenth) {return this.parseBcdStringFromBytes(data, startIndex, lenth, null);}private String parseBcdStringFromBytes(byte[] data, int startIndex, int lenth, String defaultVal) {try {byte[] tmp = new byte[lenth];System.arraycopy(data, startIndex, tmp, 0, lenth);return this.bcd8421Operater.bcd2String(tmp);} catch (Exception e) {log.error("解析BCD(8421码)出错:{}", e.getMessage());e.printStackTrace();return defaultVal;}}private int parseIntFromBytes(byte[] data, int startIndex, int length) {return this.parseIntFromBytes(data, startIndex, length, 0);}private int parseIntFromBytes(byte[] data, int startIndex, int length, int defaultVal) {try {// 字节数大于4,从起始索引开始向后处理4个字节,其余超出部分丢弃final int len = length > 4 ? 4 : length;byte[] tmp = new byte[len];System.arraycopy(data, startIndex, tmp, 0, len);return bitOperator.byteToInteger(tmp);} catch (Exception e) {log.error("解析整数出错:{}", e.getMessage());e.printStackTrace();return defaultVal;}}
}

2.2.2 用到的工具类

2.2.2.1 BCD操作工具类

package cn.hylexus.jt808.util;public class BCD8421Operater {/*** BCD字节数组===>String* * @param bytes* @return 十进制字符串*/public String bcd2String(byte[] bytes) {StringBuilder temp = new StringBuilder(bytes.length * 2);for (int i = 0; i < bytes.length; i++) {// 高四位temp.append((bytes[i] & 0xf0) >>> 4);// 低四位temp.append(bytes[i] & 0x0f);}return temp.toString().substring(0, 1).equalsIgnoreCase("0") ? temp.toString().substring(1) : temp.toString();}/*** 字符串==>BCD字节数组* * @param str* @return BCD字节数组*/public byte[] string2Bcd(String str) {// 奇数,前补零if ((str.length() & 0x1) == 1) {str = "0" + str;}byte ret[] = new byte[str.length() / 2];byte bs[] = str.getBytes();for (int i = 0; i < ret.length; i++) {byte high = ascII2Bcd(bs[2 * i]);byte low = ascII2Bcd(bs[2 * i + 1]);// TODO 只遮罩BCD低四位?ret[i] = (byte) ((high << 4) | low);}return ret;}private byte ascII2Bcd(byte asc) {if ((asc >= '0') && (asc <= '9'))return (byte) (asc - '0');else if ((asc >= 'A') && (asc <= 'F'))return (byte) (asc - 'A' + 10);else if ((asc >= 'a') && (asc <= 'f'))return (byte) (asc - 'a' + 10);elsereturn (byte) (asc - 48);}
}

2.2.2.2 位操作工具类

package cn.hylexus.jt808.util;import java.util.Arrays;
import java.util.List;public class BitOperator {/*** 把一个整形该为byte* * @param value* @return* @throws Exception*/public byte integerTo1Byte(int value) {return (byte) (value & 0xFF);}/*** 把一个整形该为1位的byte数组* * @param value* @return* @throws Exception*/public byte[] integerTo1Bytes(int value) {byte[] result = new byte[1];result[0] = (byte) (value & 0xFF);return result;}/*** 把一个整形改为2位的byte数组* * @param value* @return* @throws Exception*/public byte[] integerTo2Bytes(int value) {byte[] result = new byte[2];result[0] = (byte) ((value >>> 8) & 0xFF);result[1] = (byte) (value & 0xFF);return result;}/*** 把一个整形改为3位的byte数组* * @param value* @return* @throws Exception*/public byte[] integerTo3Bytes(int value) {byte[] result = new byte[3];result[0] = (byte) ((value >>> 16) & 0xFF);result[1] = (byte) ((value >>> 8) & 0xFF);result[2] = (byte) (value & 0xFF);return result;}/*** 把一个整形改为4位的byte数组* * @param value* @return* @throws Exception*/public byte[] integerTo4Bytes(int value){byte[] result = new byte[4];result[0] = (byte) ((value >>> 24) & 0xFF);result[1] = (byte) ((value >>> 16) & 0xFF);result[2] = (byte) ((value >>> 8) & 0xFF);result[3] = (byte) (value & 0xFF);return result;}/*** 把byte[]转化位整形,通常为指令用* * @param value* @return* @throws Exception*/public int byteToInteger(byte[] value) {int result;if (value.length == 1) {result = oneByteToInteger(value[0]);} else if (value.length == 2) {result = twoBytesToInteger(value);} else if (value.length == 3) {result = threeBytesToInteger(value);} else if (value.length == 4) {result = fourBytesToInteger(value);} else {result = fourBytesToInteger(value);}return result;}/*** 把一个byte转化位整形,通常为指令用* * @param value* @return* @throws Exception*/public int oneByteToInteger(byte value) {return (int) value & 0xFF;}/*** 把一个2位的数组转化位整形* * @param value* @return* @throws Exception*/public int twoBytesToInteger(byte[] value) {// if (value.length < 2) {// throw new Exception("Byte array too short!");// }int temp0 = value[0] & 0xFF;int temp1 = value[1] & 0xFF;return ((temp0 << 8) + temp1);}/*** 把一个3位的数组转化位整形* * @param value* @return* @throws Exception*/public int threeBytesToInteger(byte[] value) {int temp0 = value[0] & 0xFF;int temp1 = value[1] & 0xFF;int temp2 = value[2] & 0xFF;return ((temp0 << 16) + (temp1 << 8) + temp2);}/*** 把一个4位的数组转化位整形,通常为指令用* * @param value* @return* @throws Exception*/public int fourBytesToInteger(byte[] value) {// if (value.length < 4) {// throw new Exception("Byte array too short!");// }int temp0 = value[0] & 0xFF;int temp1 = value[1] & 0xFF;int temp2 = value[2] & 0xFF;int temp3 = value[3] & 0xFF;return ((temp0 << 24) + (temp1 << 16) + (temp2 << 8) + temp3);}/*** 把一个4位的数组转化位整形* * @param value* @return* @throws Exception*/public long fourBytesToLong(byte[] value) throws Exception {// if (value.length < 4) {// throw new Exception("Byte array too short!");// }int temp0 = value[0] & 0xFF;int temp1 = value[1] & 0xFF;int temp2 = value[2] & 0xFF;int temp3 = value[3] & 0xFF;return (((long) temp0 << 24) + (temp1 << 16) + (temp2 << 8) + temp3);}/*** 把一个数组转化长整形* * @param value* @return* @throws Exception*/public long bytes2Long(byte[] value) {long result = 0;int len = value.length;int temp;for (int i = 0; i < len; i++) {temp = (len - 1 - i) * 8;if (temp == 0) {result += (value[i] & 0x0ff);} else {result += (value[i] & 0x0ff) << temp;}}return result;}/*** 把一个长整形改为byte数组* * @param value* @return* @throws Exception*/public byte[] longToBytes(long value){return longToBytes(value, 8);}/*** 把一个长整形改为byte数组* * @param value* @return* @throws Exception*/public byte[] longToBytes(long value, int len) {byte[] result = new byte[len];int temp;for (int i = 0; i < len; i++) {temp = (len - 1 - i) * 8;if (temp == 0) {result[i] += (value & 0x0ff);} else {result[i] += (value >>> temp) & 0x0ff;}}return result;}/*** 得到一个消息ID* * @return* @throws Exception*/public byte[] generateTransactionID() throws Exception {byte[] id = new byte[16];System.arraycopy(integerTo2Bytes((int) (Math.random() * 65536)), 0, id, 0, 2);System.arraycopy(integerTo2Bytes((int) (Math.random() * 65536)), 0, id, 2, 2);System.arraycopy(integerTo2Bytes((int) (Math.random() * 65536)), 0, id, 4, 2);System.arraycopy(integerTo2Bytes((int) (Math.random() * 65536)), 0, id, 6, 2);System.arraycopy(integerTo2Bytes((int) (Math.random() * 65536)), 0, id, 8, 2);System.arraycopy(integerTo2Bytes((int) (Math.random() * 65536)), 0, id, 10, 2);System.arraycopy(integerTo2Bytes((int) (Math.random() * 65536)), 0, id, 12, 2);System.arraycopy(integerTo2Bytes((int) (Math.random() * 65536)), 0, id, 14, 2);return id;}/*** 把IP拆分位int数组* * @param ip* @return* @throws Exception*/public int[] getIntIPValue(String ip) throws Exception {String[] sip = ip.split("[.]");// if (sip.length != 4) {// throw new Exception("error IPAddress");// }int[] intIP = { Integer.parseInt(sip[0]), Integer.parseInt(sip[1]), Integer.parseInt(sip[2]),Integer.parseInt(sip[3]) };return intIP;}/*** 把byte类型IP地址转化位字符串* * @param address* @return* @throws Exception*/public String getStringIPValue(byte[] address) throws Exception {int first = this.oneByteToInteger(address[0]);int second = this.oneByteToInteger(address[1]);int third = this.oneByteToInteger(address[2]);int fourth = this.oneByteToInteger(address[3]);return first + "." + second + "." + third + "." + fourth;}/*** 合并字节数组* * @param first* @param rest* @return*/public byte[] concatAll(byte[] first, byte[]... rest) {int totalLength = first.length;for (byte[] array : rest) {if (array != null) {totalLength += array.length;}}byte[] result = Arrays.copyOf(first, totalLength);int offset = first.length;for (byte[] array : rest) {if (array != null) {System.arraycopy(array, 0, result, offset, array.length);offset += array.length;}}return result;}/*** 合并字节数组* * @param rest* @return*/public byte[] concatAll(List<byte[]> rest) {int totalLength = 0;for (byte[] array : rest) {if (array != null) {totalLength += array.length;}}byte[] result = new byte[totalLength];int offset = 0;for (byte[] array : rest) {if (array != null) {System.arraycopy(array, 0, result, offset, array.length);offset += array.length;}}return result;}public float byte2Float(byte[] bs) {return Float.intBitsToFloat((((bs[3] & 0xFF) << 24) + ((bs[2] & 0xFF) << 16) + ((bs[1] & 0xFF) << 8) + (bs[0] & 0xFF)));}public float byteBE2Float(byte[] bytes) {int l;l = bytes[0];l &= 0xff;l |= ((long) bytes[1] << 8);l &= 0xffff;l |= ((long) bytes[2] << 16);l &= 0xffffff;l |= ((long) bytes[3] << 24);return Float.intBitsToFloat(l);}public int getCheckSum4JT808(byte[] bs, int start, int end) {if (start < 0 || end > bs.length)throw new ArrayIndexOutOfBoundsException("getCheckSum4JT808 error : index out of bounds(start=" + start+ ",end=" + end + ",bytes length=" + bs.length + ")");int cs = 0;for (int i = start; i < end; i++) {cs ^= bs[i];}return cs;}public int getBitRange(int number, int start, int end) {if (start < 0)throw new IndexOutOfBoundsException("min index is 0,but start = " + start);if (end >= Integer.SIZE)throw new IndexOutOfBoundsException("max index is " + (Integer.SIZE - 1) + ",but end = " + end);return (number << Integer.SIZE - (end + 1)) >>> Integer.SIZE - (end - start + 1);}public int getBitAt(int number, int index) {if (index < 0)throw new IndexOutOfBoundsException("min index is 0,but " + index);if (index >= Integer.SIZE)throw new IndexOutOfBoundsException("max index is " + (Integer.SIZE - 1) + ",but " + index);return ((1 << index) & number) >> index;}public int getBitAtS(int number, int index) {String s = Integer.toBinaryString(number);return Integer.parseInt(s.charAt(index) + "");}@Deprecatedpublic int getBitRangeS(int number, int start, int end) {String s = Integer.toBinaryString(number);StringBuilder sb = new StringBuilder(s);while (sb.length() < Integer.SIZE) {sb.insert(0, "0");}String tmp = sb.reverse().substring(start, end + 1);sb = new StringBuilder(tmp);return Integer.parseInt(sb.reverse().toString(), 2);}
}

2.3 和netty结合

2.3.1 netty处理器链

import java.util.concurrent.TimeUnit;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;import cn.kkbc.tpms.tcp.service.TCPServerHandler;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.Unpooled;
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.codec.DelimiterBasedFrameDecoder;
import io.netty.handler.timeout.IdleStateHandler;
import io.netty.util.concurrent.Future;public class TCPServer2 {private Logger log = LoggerFactory.getLogger(getClass());private volatile boolean isRunning = false;private EventLoopGroup bossGroup = null;private EventLoopGroup workerGroup = null;private int port;public TCPServer2() {}public TCPServer2(int port) {this();this.port = port;}private void bind() throws Exception {this.bossGroup = new NioEventLoopGroup();this.workerGroup = new NioEventLoopGroup();ServerBootstrap serverBootstrap = new ServerBootstrap();serverBootstrap.group(bossGroup, workerGroup)//.channel(NioServerSocketChannel.class) //.childHandler(new ChannelInitializer<SocketChannel>() { //@Overridepublic void initChannel(SocketChannel ch) throws Exception {//超过15分钟未收到客户端消息则自动断开客户端连接ch.pipeline().addLast("idleStateHandler",new IdleStateHandler(15, 0, 0, TimeUnit.MINUTES));//ch.pipeline().addLast(new Decoder4LoggingOnly());// 1024表示单条消息的最大长度，解码器在查找分隔符的时候，达到该长度还没找到的话会抛异常ch.pipeline().addLast(new DelimiterBasedFrameDecoder(1024, Unpooled.copiedBuffer(new byte[] { 0x7e }),Unpooled.copiedBuffer(new byte[] { 0x7e, 0x7e })));ch.pipeline().addLast(new TCPServerHandler());}}).option(ChannelOption.SO_BACKLOG, 128) //.childOption(ChannelOption.SO_KEEPALIVE, true);this.log.info("TCP服务启动完毕,port={}", this.port);ChannelFuture channelFuture = serverBootstrap.bind(port).sync();channelFuture.channel().closeFuture().sync();}public synchronized void startServer() {if (this.isRunning) {throw new IllegalStateException(this.getName() + " is already started .");}this.isRunning = true;new Thread(() -> {try {this.bind();} catch (Exception e) {this.log.info("TCP服务启动出错:{}", e.getMessage());e.printStackTrace();}}, this.getName()).start();}public synchronized void stopServer() {if (!this.isRunning) {throw new IllegalStateException(this.getName() + " is not yet started .");}this.isRunning = false;try {Future<?> future = this.workerGroup.shutdownGracefully().await();if (!future.isSuccess()) {log.error("workerGroup 无法正常停止:{}", future.cause());}future = this.bossGroup.shutdownGracefully().await();if (!future.isSuccess()) {log.error("bossGroup 无法正常停止:{}", future.cause());}} catch (InterruptedException e) {e.printStackTrace();}this.log.info("TCP服务已经停止...");}private String getName() {return "TCP-Server";}public static void main(String[] args) throws Exception {TCPServer2 server = new TCPServer2(20048);server.startServer();// Thread.sleep(3000);// server.stopServer();}}

2.3.2 netty针对于JT808的消息处理器

package cn.hylexus.jt808.service;import org.slf4j.Logger;
import org.slf4j.LoggerFactory;import cn.hylexus.jt808.server.SessionManager;
import cn.hylexus.jt808.service.codec.MsgDecoder;
import cn.hylexus.jt808.vo.PackageData;
import cn.hylexus.jt808.vo.Session;
import io.netty.buffer.ByteBuf;
import io.netty.channel.ChannelHandlerContext;
import io.netty.channel.ChannelInboundHandlerAdapter;
import io.netty.handler.timeout.IdleState;
import io.netty.handler.timeout.IdleStateEvent;
import io.netty.util.ReferenceCountUtil;public class TCPServerHandler extends ChannelInboundHandlerAdapter { // (1)private final Logger logger = LoggerFactory.getLogger(getClass());// 一个维护客户端连接的类private final SessionManager sessionManager;private MsgDecoder decoder = new MsgDecoder();public TCPServerHandler() {this.sessionManager = SessionManager.getInstance();}@Overridepublic void channelRead(ChannelHandlerContext ctx, Object msg) throws InterruptedException { // (2)try {ByteBuf buf = (ByteBuf) msg;if (buf.readableBytes() <= 0) {// ReferenceCountUtil.safeRelease(msg);return;}byte[] bs = new byte[buf.readableBytes()];buf.readBytes(bs);PackageData jt808Msg = this.decoder.queueElement2PackageData(bs);// 处理客户端消息this.processClientMsg(jt808Msg);} finally {release(msg);}}private void processClientMsg(PackageData jt808Msg) {// TODO 更加消息ID的不同,分别实现自己的业务逻辑if (jt808Msg.getMsgHeader().getMsgId() == 0x900) {// TODO ...} else if (jt808Msg.getMsgHeader().getMsgId() == 0x9001) {// TODO ...}// else if(){}// else if(){}// else if(){}// else if(){}// ...else {logger.error("位置消息,消息ID={}", jt808Msg.getMsgHeader().getMsgId());}}@Overridepublic void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) { // (4)logger.error("发生异常:{}", cause.getMessage());cause.printStackTrace();}@Overridepublic void channelActive(ChannelHandlerContext ctx) throws Exception {Session session = Session.buildSession(ctx.channel());sessionManager.put(session.getId(), session);logger.debug("终端连接:{}", session);}@Overridepublic void channelInactive(ChannelHandlerContext ctx) throws Exception {final String sessionId = ctx.channel().id().asLongText();Session session = sessionManager.findBySessionId(sessionId);this.sessionManager.removeBySessionId(sessionId);logger.debug("终端断开连接:{}", session);ctx.channel().close();// ctx.close();}@Overridepublic void userEventTriggered(ChannelHandlerContext ctx, Object evt) throws Exception {if (IdleStateEvent.class.isAssignableFrom(evt.getClass())) {IdleStateEvent event = (IdleStateEvent) evt;if (event.state() == IdleState.READER_IDLE) {Session session = this.sessionManager.removeBySessionId(Session.buildId(ctx.channel()));logger.error("服务器主动断开连接:{}", session);ctx.close();}}}private void release(Object msg) {try {ReferenceCountUtil.release(msg);} catch (Exception e) {e.printStackTrace();}}
}

2.3.3 用到的其他类

package cn.hylexus.jt808.server;import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.function.BiConsumer;
import java.util.stream.Collectors;import cn.hylexus.jt808.vo.Session;public class SessionManager {private static volatile SessionManager instance = null;// netty生成的sessionID和Session的对应关系private Map<String, Session> sessionIdMap;// 终端手机号和netty生成的sessionID的对应关系private Map<String, String> phoneMap;public static SessionManager getInstance() {if (instance == null) {synchronized (SessionManager.class) {if (instance == null) {instance = new SessionManager();}}}return instance;}public SessionManager() {this.sessionIdMap = new ConcurrentHashMap<>();this.phoneMap = new ConcurrentHashMap<>();}public boolean containsKey(String sessionId) {return sessionIdMap.containsKey(sessionId);}public boolean containsSession(Session session) {return sessionIdMap.containsValue(session);}public Session findBySessionId(String id) {return sessionIdMap.get(id);}public Session findByTerminalPhone(String phone) {String sessionId = this.phoneMap.get(phone);if (sessionId == null)return null;return this.findBySessionId(sessionId);}public synchronized Session put(String key, Session value) {if (value.getTerminalPhone() != null && !"".equals(value.getTerminalPhone().trim())) {this.phoneMap.put(value.getTerminalPhone(), value.getId());}return sessionIdMap.put(key, value);}public synchronized Session removeBySessionId(String sessionId) {if (sessionId == null)return null;Session session = sessionIdMap.remove(sessionId);if (session == null)return null;if (session.getTerminalPhone() != null)this.phoneMap.remove(session.getTerminalPhone());return session;}public Set<String> keySet() {return sessionIdMap.keySet();}public void forEach(BiConsumer<? super String, ? super Session> action) {sessionIdMap.forEach(action);}public Set<Entry<String, Session>> entrySet() {return sessionIdMap.entrySet();}public List<Session> toList() {return this.sessionIdMap.entrySet().stream().map(e -> e.getValue()).collect(Collectors.toList());}}

3 demo级别java示例

请移步: https://github.com/hylexus/jt-808-protocol

另请不要吝啬，在GitHub给个star让小可装装逼…………^_^

注

急急忙忙写的博客，先写个大致的思路,有疑问可以联系本人，联系方式：

emial: hylexus@163.com

java解析JT808协议相关推荐

Java解析JT808协议示例
原文地址:https://blog.csdn.net/hylexus/article/details/54987786 JT808协议扫盲 1 数据类型 2 消息结构 3 消息头解析 1 消息体实体 ...
Netty解析JT808协议
原文地址:http://blog.csdn.net/hylexus/article/details/54987786 1 JT808协议扫盲 1.1 数据类型数据类型描述及要求 BYTE 无符号单 ...
java解析电力协议_DLT645解析JAVA JAVA解析DLT645电表通信协议 - 下载 - 搜珍网
压缩包 : d49c1cc60d68dfaef4a4b19567ae9131.zip 列表 ProtocolAnalysls-master/ ProtocolAnalysls-master/.giti ...
java解析bt协议详解_【转】bt协议的详细分析
一 BT系统的组成结构 1 普通的Web服务器: 例如Apache或IIS服务器 2 一个静态的种子文件: 即.Torrent文件,采用Bencoding编码 3 Tracke ...
java解析bt协议详解_BT（带中心Tracker）通信协议的分析
BT通信协议举例分析现在的很多BT下载都采用了DHT网络,这样进行BT下载就不需要中心服务器了.本文针对的是需要中心服务器的BT下载. 小弟我最近正在研究BT通信协议,网上的资料很全,但是不是那事详 ...
java解析bt协议详解_BT下载原理分析
BT全名为BitTorrent,是一个p2p软件,你在下载download的同时,也在为其他用户提供上传upload,因为大家是"互相帮助",所以不会随着用户数的增加而降低下载速度 ...
JAVA实现报文解析：协议的数据类型和完整的报文结构解析
**JAVA实现GBT32960报文解析系列文章链接:** JAVA实现GBT32960报文解析(一):协议的数据类型和完整的报文结构解析 JAVA实现GBT32960报文解析(二):数据包结构解析源 ...
app及Java服务端实现JT808协议的定义解析
app及Java服务端实现JT808协议的定义解析,可以用做行车记录仪等的app. 网上很多帖子已经对JT808协议做了说明,我在这里就不做过多的赘述了. 最近接到一个项目是打车类的,所以对这协议做了 ...
java jt808协议解读_jt808 协议服务端解析 - 下载 - 搜珍网
文件名大小更新时间 jt808\.git\config3022019-11-09 jt808\.git\description732019-11-09 jt808\.git\HEAD232019-11 ...

java解析JT808协议