欢迎您访问程序员文章站本站旨在为大家提供分享程序员计算机编程知识!
您现在的位置是: 首页  >  IT编程

Java自定义协议报文封装 添加Crc32校验的实例

程序员文章站 2023-12-15 19:00:34
刚做完的demo,直接进入主题了,开启两个线程,模拟socket服务端和客户端通信,将数据封装为指定格式报文发送 代码: import java.io.ioex...

刚做完的demo,直接进入主题了,开启两个线程,模拟socket服务端和客户端通信,将数据封装为指定格式报文发送

代码:

import java.io.ioexception;
import java.io.inputstream;
import java.io.outputstream;
import java.net.inetaddress;
import java.net.serversocket;
import java.net.socket;
import java.net.unknownhostexception;
/**
 * created by sikang on 2016/4/29.
 */
public class customdata {
 public static void main(string args[]) {
  //服务端线程
  new thread(new runnable() {
   @override
   public void run() {
    try {
     //开启服务端socket
     serversocket server = new serversocket(9000);
     //等待客户端连接
     socket socket = server.accept();
     inputstream inputstream = socket.getinputstream();
     //先得到前两个字节 为报文长度
     byte[] lenbytes = new byte[2];
     inputstream.read(lenbytes);
     short length = bytestoshort(lenbytes);
   system.out.println("length: " + length);
     //然后得到接下来的四个字节 crc32校验码
     byte[] crc = new byte[4];
     inputstream.read(crc);
     int crc32 = bytestoint(crc);
     //得到剩下的字段 ver、cmd、data
     byte[] bytes = new byte[length - 2 - 4];
     inputstream.read(bytes);
     //根据得到的bytes获取新的crc32校验码 验证数据是否完整(可以在读取bytes时少读一位,看看能不能通过)
     if (crc32 == getcrc32(bytes)) {
      system.out.println("crc32 right!");
     }else{
   system.out.println("crc32 error!");
      return;
   }
     //取出ver cmd
     int ver = integer.parseint(bytetohex(bytes[0]), 16);
     int cmd = integer.parseint(bytetohex(bytes[1]), 16);
     //看看ver是否是客户端发送0x05
     if (ver == 0x05) {
      system.out.println("ver: 0x05");
     }
     //cmd是否是客户端发送0xff
     if (cmd == 0xff) {
      system.out.println("cmd: 0xff");
     }
     //得到剩下的数据字节数,取出data数据
     int datalen = length - 2 - 4 - 1 - 1;
     byte[] data = new byte[datalen];
     int index = 1;
     for (int i = 0; i < datalen; i++) {
      data[i] = bytes[++index];
     }
     string str = new string(data);
     system.out.println("data: " + str);
     inputstream.close();
    } catch (ioexception e) {
     e.printstacktrace();
    }
   }
  }).start();
  //客户端线程
  new thread(new runnable() {
   @override
   public void run() {
    try {
     //连接服务端
     socket socket = new socket(getipaddress(), 9000);
     outputstream outputstream = socket.getoutputstream();
     string str = "hellow world!";
     byte[] data = str.getbytes();
     //发送报文
     pack(outputstream, (byte) 0xff, data, data.length);
     outputstream.flush();
     outputstream.close();
    } catch (ioexception e) {
     e.printstacktrace();
    }
   }
  }).start();
 }
 /**
 *封装并发送报文
 *这里报文格式为{报文总长度[2字节],crc32校验码[4字节],ver版本信息[1字节],cmd指令[1字节],data数据内容[若干字节]}
 */
 private static void pack(outputstream out, byte cmd, byte[] data, int len) {
  try {
   //先得到报文总长度,如上介绍的格式 字节数相加
   short totalsize = (short) (2 + 4 + 1 + 1 + len);
   //输出报文长度
   out.write(shorttobyte(totalsize), 0, 2);
   //需要校验的字段
   byte[] bytes = new byte[1 + 1 + len];
   int index = 0;
   bytes[index++] = 0x05;//版本号(这里是写死的)
   bytes[index++] = cmd;//cmd指令
   //数据内容
   for (int i = 0; i < len; i++) {
    bytes[index++] = data[i];
   }
   //得到ver、cmd、data的crc32校验码(crc32算法在最下边,网上找的.....)
   byte[] crc32 = inttobytes(getcrc32(bytes));
   //输出crc校验码
   out.write(crc32, 0, crc32.length);
   //输出ver、cmd、data
   out.write(bytes, 0, bytes.length);
  } catch (ioexception e) {
   e.printstacktrace();
  }
 }

 /**
  * 得到本机ip
  */
 private static string getipaddress() throws unknownhostexception {
  inetaddress address = inetaddress.getlocalhost();
  return address.gethostaddress();
 }
 /**
  * int转byte[]
  */
 public static byte[] inttobytes(int value) {
  byte[] bytes = new byte[4];
  bytes[3] = (byte) (value >> 24);
  bytes[2] = (byte) (value >> 16);
  bytes[1] = (byte) (value >> 8);
  bytes[0] = (byte) (value >> 0);
  return bytes;
 }
 /**
  * short转byte[]
  */
 public static byte[] shorttobyte(short value) {
  byte[] bytes = new byte[2];
  bytes[1] = (byte) (value >> 8);
  bytes[0] = (byte) (value >> 0);
  return bytes;
 }
 /**
  * byte转16进制
  */
 public static string bytetohex(byte b) {
  int i = b & 0xff;
  return integer.tohexstring(i);
 }
 /**
  * byte[]转int
  */
 public static int bytestoint(byte[] bytes) {
  return (int) ((((bytes[3] & 0xff) << 24)
    | ((bytes[2] & 0xff) << 16)
    | ((bytes[1] & 0xff) << 8) | ((bytes[0] & 0xff) << 0)));
 }
 /**
  * byte[]转short
  */
 public static short bytestoshort(byte[] bytes) {
  return (short) (((bytes[1] << 8) | bytes[0] & 0xff));
 }
 /**
  * 得到crc32校验码
  */
 public static int getcrc32(byte[] bytes) {
  int[] table = {
    0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
    0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
    0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
    0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
    0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
    0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
    0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
    0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
    0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
    0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
    0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
    0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
    0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
    0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
    0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
    0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
    0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
    0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
    0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
    0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
    0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
    0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
    0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
    0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
    0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
    0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
    0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
    0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
    0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
    0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
    0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
    0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d,
  };
  int crc = 0xffffffff;
  for (byte b : bytes) {
   crc = (crc >>> 8 ^ table[(crc ^ b) & 0xff]);
  }
  crc = crc ^ 0xffffffff;
  return crc;
 }
}

运行结果:

Java自定义协议报文封装 添加Crc32校验的实例

以上这篇java自定义协议报文封装 添加crc32校验的实例就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持。

上一篇:

下一篇: